Title: CSS Text Module Level 3
Shortname: css-text
Level: 3
Status: ED
Work Status: Testing
Group: csswg
ED: https://drafts.csswg.org/css-text-3/
TR: https://www.w3.org/TR/css-text-3/
Previous version: https://www.w3.org/TR/2023/CRD-css-text-3-20230903/
Test Suite: http://test.csswg.org/suites/css3-text/nightly-unstable/
!Test Coverage Analysis: https://drafts.csswg.org/css-text-3/test-coverage
Implementation Report: https://test.csswg.org/harness/results/css-text-3_dev/grouped/
Editor: Elika J. Etemad / fantasai, Apple, http://fantasai.inkedblade.net/contact, w3cid 35400
Editor: Koji Ishii, Invited Expert, kojiishi@gluesoft.co.jp, w3cid 45369
Editor: Florian Rivoal, Invited Expert, https://florian.rivoal.net, w3cid 43241
Abstract: This CSS module defines properties for text manipulation and specifies their processing model. It covers line breaking, justification and alignment, white space handling, and text transformation.
At Risk: the ''full-width'' value of 'text-transform'
At Risk: the ''full-size-kana'' value of 'text-transform'
At Risk: the <length> values of the 'tab-size' property
At Risk: the 'text-justify' property
At Risk: the 'hanging-punctuation' property
At Risk: Writing-system specific adjustments to line-breaking
At Risk: Trimming trailing Ogham space marks
Ignored Vars: letter-spacing
WPT Path Prefix: /css/css-text/

Introduction

This module describes the typesetting controls of CSS; that is, the features of CSS that control the translation of source text to formatted, line-wrapped text. Various CSS properties provide control over [[#transforming|case transformation]], [[#white-space-processing|white space collapsing]], [[#white-space-property|text wrapping]], [[#line-breaking|line breaking rules]] and [[#hyphenation|hyphenation]], [[#justification|alignment and justification]], [[#spacing|spacing]], and [[#edge-effects|indentation]].
Note: Font selection is covered in the CSS Fonts Module. [[CSS-FONTS-3]] Features for decorating text, such as [[css-text-decor-3#line-decoration|underlines]], [[css-text-decor-3#emphasis-marks|emphasis marks]], and [[css-text-decor-3#text-shadow-property|shadows]], (previously part of this module) are covered in the CSS Text Decoration Module. [[CSS-TEXT-DECOR-3]] [[css-writing-modes-4#text-direction|Bidirectional]] and [[css-writing-modes-4#vertical-intro|vertical]] text are addressed in the CSS Writing Modes Module. [[CSS-WRITING-MODES-4]].
Further information about the typesetting requirements of various languages and writing systems around the world can be found in the Internationalization Working Group’s Language Enablement Index. [[TYPOGRAPHY]] removing-collapsible-crash.html removing-collapsible-spaces-before-float-crash.html crashtests/line-break-float-crash.html crashtests/trailing-space-with-cr-crash.html ellisize-rtl-text-crash.html altering-dom-crash.html whitespace-followed-by-cham-symbol-crash.html white-space/append-whitespace-only-node-crash-001.html crashtests/rendering-rtl-bidi-override-crash.html crashtests/rendering-table-caption-with-list-item-and-svg-crash.html crashtests/rendering-table-caption-with-negative-margins-crash.html crashtests/white-space-pre-wrap-chash.html crashtests/word-spacing-large-value.html crashtests/eol-spaces-bidi-min-content-crash.html crashtests/overflow-wrap-anywhere-crash.html crashtests/text-indent-each-line-crash.html overflow-wrap/crashtests/overflow-wrap-leading-floats-crash.html text-autospace/crashtests/text-autospace-shape-cache-crash.html text-indent/text-indent-ruby-crash.html

Module Interactions

This module, together with the CSS Text Decoration Module, replaces and extends the text-level features defined in Cascading Style Sheets Level 2 chapter 16. [[CSS-TEXT-DECOR-3]] [[!CSS2]] In addition to the terms defined below, other terminology and concepts used in this specification are defined in Cascading Style Sheets Level 2 and the CSS Writing Modes Module. [[!CSS2]] and [[!CSS-WRITING-MODES-4]].

Value Definitions

This specification follows the [[CSS2/about#property-defs|CSS property definition conventions]] from [[!CSS2]] using the [[css-values-3#value-defs|value definition syntax]] from [[!CSS-VALUES-3]]. Value types not defined in this specification are defined in CSS Values & Units [[!CSS-VALUES-3]]. Combination with other CSS modules may expand the definitions of these value types. In addition to the property-specific values listed in their definitions, all properties defined in this specification also accept the [=CSS-wide keywords=] as their property value. For readability they have not been repeated explicitly.

Languages and Typesetting

Authors should accurately language-tag their content for the best typographic behavior. Many typographic effects vary by linguistic context. Language and writing system conventions can affect line breaking, hyphenation, justification, glyph selection, and many other typographic effects. In CSS, language-specific typographic tailorings are only applied when the [=content language=] is known (declared). Therefore, higher quality typography requires authors to communicate to the UA the correct linguistic context of the text in the document. The content language of an element is the (human) language the element is declared to be in, according to the rules of the [=document language=]. Note that it is possible for the [=content language=] of an element to be unknown-- e.g. untagged content, or content in a [=document language=] that does not have a language-tagging facility, is considered to have an unknown [=content language=]. Note: Authors can declare the [=content language=] using the global lang attribute in HTML or the universal xml:lang attribute in XML. See the rules for determining the content language of an HTML element in HTML, and the [[XML#sec-lang-tag|rules for determining the content language of an XML element]] in XML 1.0. [[HTML]] [[XML10]] The [=content language=] an element is declared to be in also identifies the specific written form of that language used in that element, known as the content writing system. Depending on the [=document language=]’s facilities for identifying the [=content language=], this information can be explicit or implied. See the normative [[#script-tagging]]. Note: Some languages have more than one writing system tradition; in other cases a language can be transliterated into a foreign writing system. Authors should [[#script-tagging|subtag]] such cases so that the UA can adapt appropriately.

For example, Korean (ko) can be written in Hangul (-Hang), Hanja (-Hani), or a combination (-Kore). Historical documents written solely in Hanja do not use word spaces and are formatted more like modern Chinese than modern Korean. In other words, for typographic purposes ko-Hani behaves more like zh-Hant than ko (ko-Kore). As another example Japanese (ja) is typically written in a combination (-Japn) of Hiragana (-Hira), Katakana (-Kana), and Kanji (-Hani). However, it can also be “romanized” into Latin (-Latn) for special purposes like language-learning textbooks, in which case it should be formatted more like English than Japanese. As a third example contemporary Mongolian is written in two scripts: Cyrillic (-Cyrl, officially used in Mongolia) and Mongolian (-Mong, more common in Inner Mongolia, part of China). These have very different formatting requirements, with Cyrillic behaving similar to Latin and Greek, and Mongolian deriving from both Arabic and Chinese writing conventions.

Characters and Letters

The basic unit of typesetting is the character. However, because writing systems are not always as simple as the basic English alphabet, what a [=character=] actually is depends on the context in which the term is used. For example, in Hangul (the Korean writing system), each square representation of a syllable (e.g. =Han) can be considered a character. However, the square symbol is really composed of multiple letters each representing a phoneme (e.g. =h, =a, =n) and these also could each be considered a character. A basic unit of computer text encoding, for any given encoding, is also called a [=character=], and depending on the encoding, a single encoding [=character=] might correspond to the entire pre-composed syllabic [=character=] (e.g. ), to the individual phonemic [=character=] (e.g. ), or to smaller units such as a base letterform (e.g. ) and any combining marks that vary it (e.g. extra strokes that represent aspiration). In turn, a single encoding [=character=] can be represented in the data stream as one or more bytes; and in programming environments one byte is sometimes also called a [=character=]. Therefore the term [=character=] is fairly ambiguous where technical precision is required. For text layout, we will refer to the typographic character unit as the basic unit of text. Even within the realm of text layout, the relevant [=character=] unit depends on the operation. For example, line-breaking and letter-spacing will segment a sequence of Thai characters that include U+0E33  ำ THAI CHARACTER SARA AM differently; or the behavior of a conjunct consonant in a script such as Devanagari may depend on the font in use. So the [=typographic character=] represents a unit of the writing system-- such as a Latin alphabetic letter (including its diacritics), Hangul syllable, Chinese ideographic character, Myanmar syllable cluster-- that is indivisible with respect to a particular typographic operation (line-breaking, first-letter effects, tracking, justification, vertical arrangement, etc.). word-break/word-break-break-all-007.html word-break/word-break-break-all-008.html Unicode Standard Annex #29: Text Segmentation defines a unit called the grapheme cluster which approximates the [=typographic character=]. [[!UAX29]] A UA must use the extended grapheme cluster (not legacy grapheme cluster), as defined in UAX29, as the basis for its [=typographic character unit=]. However, the UA should tailor the definitions as required by typographic tradition since the default rules are not always appropriate or ideal-- and is expected to tailor them differently depending on the operation as needed. line-breaking/line-breaking-013.html line-breaking/line-breaking-014.html Note: The rules for such tailorings are out of scope for CSS.
The following are some examples of [=typographic character unit=] tailorings required by standard typesetting practice:
A typographic letter unit (or letter for the purpose of this specification) is a [=typographic character unit=] belonging to one of the Letter or Number [=general categories=]. See [[#character-properties]] for how to determine the Unicode properties of a [=typographic character unit=]. The rendering characteristics of a [=typographic character unit=] divided by an element boundary is undefined. Ideally each component should be rendered according to the formatting requirements of its respective element’s properties while maintaining correct shaping and positioning of the [=typographic character unit=] as a whole. However, depending on the nature of the formatting differences between its parts and the capabilities of the font technology in use, this is not always possible. Therefore such a [=typographic character unit=] may be rendered as belonging to either side of the boundary, or as some approximation of belonging to both. Authors are forewarned that dividing [=grapheme clusters=] or ligatures by element boundaries may give inconsistent or undesired results.

Text Processing

CSS is built on Unicode. [[UNICODE]] UAs that support Unicode must adhere to all normative requirements of the Unicode Core Standard, except where explicitly overridden by CSS. UAs implemented on the basis of a non-Unicode text encoding model are still expected to fulfill the same text handling requirements by assuming an appropriate mapping and analogous behavior. text-encoding/shaping-join-001.html text-encoding/shaping-join-002.html text-encoding/shaping-join-003.html text-encoding/shaping-no-join-001.html text-encoding/shaping-no-join-002.html text-encoding/shaping-no-join-003.html text-encoding/shaping-tatweel-001.html text-encoding/shaping-tatweel-002.html text-encoding/shaping-tatweel-003.html shaping/shaping-arabic-diacritics-001.html shaping/shaping-arabic-diacritics-002.html white-space/full-width-leading-spaces-005.html white-space/object-replacement-1.html white-space/object-replacement-2.html white-space/white-space-vs-joiners-001.html white-space/white-space-vs-joiners-002.html For the purpose of determining adjacency for text processing (such as white space processing, text transformation, line-breaking, etc.), and thus in general within this specification, intervening [=inline box=] boundaries and [=out-of-flow=] elements must be ignored. With respect to text shaping, however, see [[#boundary-shaping]]. line-breaking/line-breaking-002.html line-breaking/line-breaking-003.html line-breaking/line-breaking-004.html line-breaking/line-breaking-005.html line-breaking/line-breaking-006.html line-breaking/line-breaking-007.html line-breaking/line-breaking-008.html word-break/word-break-min-content-002.html word-break/word-break-min-content-003.html word-break/word-break-min-content-004.html word-break/word-break-min-content-005.html overflow-wrap/overflow-wrap-anywhere-010.html white-space-processing-048.xht white-space-processing-049.xht

Transforming Text

Case Transforms: the 'text-transform' property

	Name: text-transform
	Value: none | [capitalize | uppercase | lowercase ] || full-width || full-size-kana
	Initial: none
	Applies to: text
	Inherited: yes
	Canonical order: n/a
	Computed value: specified keyword
	Animation type: discrete
	
inheritance.html parsing/text-transform-valid.html parsing/text-transform-invalid.html parsing/text-transform-computed.html text-transform/text-transform-multiple-001.html c545-txttrans-000.xht text-transform-005.xht text-transform-applies-to-001.xht text-transform-applies-to-002.xht text-transform-applies-to-003.xht text-transform-applies-to-005.xht text-transform-applies-to-006.xht text-transform-applies-to-007.xht text-transform-applies-to-008.xht text-transform-applies-to-009.xht text-transform-applies-to-010.xht text-transform-applies-to-011.xht text-transform-applies-to-012.xht text-transform-applies-to-013.xht text-transform-applies-to-014.xht text-transform-applies-to-015.xht This property transforms text for styling purposes. It has no effect on the underlying content, and must not affect the content of a plain text copy & paste operation. text-transform/text-transform-upperlower-105.html Advisement: Authors must not rely on 'text-transform' for semantic purposes; rather the correct casing and semantics should be encoded in the source document text and markup. text-transform/text-transform-copy-paste-001-manual.html Values have the following meanings:
none
No effects. text-transform/text-transform-none-001.xht text-transform-004.xht
capitalize
Puts the first [=typographic letter unit=] of each word, if lowercase, in titlecase; other characters are unaffected. text-transform/text-transform-capitalize-001.html text-transform/text-transform-capitalize-003.html text-transform/text-transform-capitalize-005.html text-transform/text-transform-capitalize-007.html text-transform/text-transform-capitalize-009.html text-transform/text-transform-capitalize-010.html text-transform/text-transform-capitalize-011.html text-transform/text-transform-capitalize-014.html text-transform/text-transform-capitalize-016.html text-transform/text-transform-capitalize-018.html text-transform/text-transform-capitalize-020.html text-transform/text-transform-capitalize-022.html text-transform/text-transform-capitalize-024.html text-transform/text-transform-capitalize-026.html text-transform/text-transform-capitalize-028.html text-transform/text-transform-capitalize-030.html text-transform/text-transform-capitalize-031.html text-transform/text-transform-capitalize-032.xht text-transform/text-transform-capitalize-034.html text-transform/text-transform-capitalize-035.html text-transform-001.xht text-transform-cap-001.xht text-transform-cap-002.xht text-transform-cap-003.xht
uppercase
Puts all [=letters=] in uppercase. text-transform/text-transform-uppercase-101.xht text-transform/text-transform-upperlower-001.html text-transform/text-transform-upperlower-003.html text-transform/text-transform-upperlower-005.html text-transform/text-transform-upperlower-007.html text-transform/text-transform-upperlower-009.html text-transform/text-transform-upperlower-011.html text-transform/text-transform-upperlower-015.html text-transform/text-transform-upperlower-017.html text-transform/text-transform-upperlower-019.html text-transform/text-transform-upperlower-021.html text-transform/text-transform-upperlower-023.html text-transform/text-transform-upperlower-025.html text-transform/text-transform-upperlower-027.html text-transform/text-transform-upperlower-029.html text-transform/text-transform-upperlower-031.html text-transform/text-transform-upperlower-044.html text-transform/text-transform-upperlower-101.html text-transform/text-transform-upperlower-103.html text-transform/text-transform-upperlower-106.html text-transform/text-transform-uppercase-dynamic.html text-transform-003.xht text-transform-bicameral-001.xht text-transform-bicameral-003.xht text-transform-bicameral-005.xht text-transform-bicameral-007.xht text-transform-bicameral-009.xht text-transform-bicameral-011.xht text-transform-bicameral-013.xht text-transform-bicameral-015.xht text-transform-bicameral-017.xht text-transform-bicameral-019.xht text-transform-bicameral-021.xht text-transform-unicase-001.xht text-transform-uppercase-001.xht text-transform-uppercase-002.xht
lowercase
Puts all [=letters=] in lowercase. text-transform/text-transform-lowercase-101.xht text-transform/text-transform-lowercase-102.xht text-transform/text-transform-upperlower-002.html text-transform/text-transform-upperlower-004.html text-transform/text-transform-upperlower-006.html text-transform/text-transform-upperlower-008.html text-transform/text-transform-upperlower-010.html text-transform/text-transform-upperlower-012.html text-transform/text-transform-upperlower-014.html text-transform/text-transform-upperlower-016.html text-transform/text-transform-upperlower-018.html text-transform/text-transform-upperlower-020.html text-transform/text-transform-upperlower-022.html text-transform/text-transform-upperlower-024.html text-transform/text-transform-upperlower-026.html text-transform/text-transform-upperlower-028.html text-transform/text-transform-upperlower-030.html text-transform/text-transform-upperlower-102.html text-transform/text-transform-upperlower-104.html text-transform-002.xht text-transform-bicameral-002.xht text-transform-bicameral-004.xht text-transform-bicameral-006.xht text-transform-bicameral-008.xht text-transform-bicameral-010.xht text-transform-bicameral-012.xht text-transform-bicameral-014.xht text-transform-bicameral-016.xht text-transform-bicameral-018.xht text-transform-bicameral-020.xht text-transform-bicameral-022.xht text-transform-lowercase-001.xht
full-width
Puts all [=typographic character units=] in [=full-width=] form. If a character does not have a corresponding [=full-width=] form, it is left as is. This value is typically used to typeset Latin letters and digits as if they were ideographic characters. text-transform/text-transform-fullwidth-001.xht text-transform/text-transform-fullwidth-002.xht text-transform/text-transform-fullwidth-004.xht text-transform/text-transform-fullwidth-005.xht
full-size-kana
Converts all [=small Kana=] characters to the equivalent [=full-size Kana=]. This value is typically used for ruby annotation text, where authors may want all small Kana to be drawn as large Kana to compensate for legibility issues at the small font sizes typically used in ruby. text-transform/text-transform-full-size-kana-001.html text-transform/text-transform-full-size-kana-002.html text-transform/text-transform-full-size-kana-003.html text-transform/text-transform-full-size-kana-004.html text-transform/text-transform-full-size-kana-005.html text-transform/text-transform-full-size-kana-006.html text-transform/text-transform-full-size-kana-007.html text-transform/text-transform-full-size-kana-008.html
The following example converts the ASCII characters used in abbreviations in Japanese text to their full-width variants so that they lay out and line break like ideographs:
abbr:lang(ja) { text-transform: full-width; }
Note: The purpose of 'text-transform' is to allow for presentational casing transformations without affecting the semantics of the document. Note in particular that 'text-transform' casing operations are lossy, and can distort the meaning of a text. While accessibility interfaces may wish to convey the apparent casing of the rendered text to the user, the transformed text cannot be relied on to accurately represent the underlying meaning of the document.
In this example, the first line of text is capitalized as a visual effect.
			section > p:first-of-type::first-line {
				text-transform: uppercase;
			}
		
This effect cannot be written into the source document because the position of the line break depends on layout. But also, the capitalization is not reflecting a semantic distinction and is not intended to affect the paragraph’s reading; therefore it belongs in the presentation layer.
In this example, the [=ruby=] annotations, which are half the size of the main paragraph text, are transformed to use regular-size kana in place of [=small kana=].
			rt { font-size: 50%; text-transform: full-size-kana; }
			:is(h1, h2, h3, h4) rt { text-transform: none; /* unset for large text*/ }
		
Note that while this makes such letters easier to see at small type sizes, the transformation distorts the text: the reader needs to mentally substitute [=small kana=] in the appropriate places-- not unlike reading a Latin inscription where all “U”s look like “V”s. For example, if ''text-transform: full-size-kana'' were applied to the following source, the annotation would read “じゆう” (jiyū), which means “liberty”, instead of “じゅう” (jū), which means “ten”, the correct reading and meaning for the annotated “十”. <ruby>十<rt>じゅう</ruby>

Mapping Rules

For ''capitalize'', what constitutes a “word“ is UA-dependent; [[!UAX29]] is suggested (but not required) for determining such word boundaries. Out-of-flow elements and inline element boundaries must not introduce a 'text-transform' word boundary and must be ignored when determining such word boundaries. text-transform/text-transform-capitalize-033.html text-transform/text-transform-capitalize-034.html text-transform/text-transform-capitalize-035.html Note: Authors cannot depend on ''capitalize'' to follow language-specific titlecasing conventions (such as skipping articles in English). The UA must use the full case mappings for Unicode characters, including any conditional casing rules, as defined in the Default Case Algorithms section of The Unicode Standard. [[!UNICODE]] If (and only if) the [=content language=] of the element is, according to the rules of the [=document language=], known, then any appropriate language-specific rules must be applied as well. These minimally include, but are not limited to, the language-specific rules in Unicode’s SpecialCasing.txt. writing-system/writing-system-text-transform-001.html text-transform/text-transform-tailoring-001.html text-transform/text-transform-tailoring-002.html text-transform/text-transform-tailoring-002a.html text-transform/text-transform-tailoring-003.html text-transform/text-transform-tailoring-004.html text-transform/text-transform-tailoring-005.html text-transform/text-transform-upperlower-032.html text-transform/text-transform-upperlower-033.html text-transform/text-transform-upperlower-034.html text-transform/text-transform-upperlower-035.html text-transform/text-transform-upperlower-038.html text-transform/text-transform-upperlower-039.html text-transform/text-transform-upperlower-040.html text-transform/text-transform-upperlower-041.html text-transform/text-transform-upperlower-042.html text-transform/text-transform-upperlower-043.html
For example, in Turkish there are two “i”s, one with a dot-- “İ” and “i”-- and one without-- “I” and “ı”. Thus the usual case mappings between “I” and “i” are replaced with a different set of mappings to their respective dotless/dotted counterparts, which do not exist in English. This mapping must only take effect if the [=content language=] is Turkish written in its modern Latin-based [=writing system=] (or another Turkic language that uses Turkish casing rules); in other languages, the usual mapping of “I” and “i” is required. This rule is thus conditionally defined in Unicode’s SpecialCasing.txt file.
text-transform-bicameral-005.xht text-transform-bicameral-006.xht The definition of full-width and half-width forms can be found in Unicode Standard Annex #11: East Asian Width. [[!UAX11]] The mapping to [=full-width=] form is defined by taking code points with the <wide> or the <narrow> tag in their Decomposition_Mapping in Unicode Standard Annex #44: Unicode Character Database. [[!UAX44]] For the <narrow> tag, the mapping is from the code point to the decomposition (minus <narrow> tag), and for the <wide> tag, the mapping is from the decomposition (minus the <wide> tag) back to the original code point. text-transform/text-transform-fullwidth-001.xht text-transform/text-transform-fullwidth-002.xht text-transform/text-transform-fullwidth-004.xht text-transform/text-transform-fullwidth-005.xht text-transform/text-transform-fullwidth-006.html text-transform/text-transform-fullwidth-007.html The mappings for [=small Kana=] to [=full-size Kana=] are defined in [[#small-kana]].

Order of Operations

When multiple values are specified and therefore multiple transformations need to be applied, they are applied in the following order:
  1. ''capitalize'', ''uppercase'', and ''lowercase''
  2. ''full-width''
  3. ''full-size-kana''
text-transform/text-transform-multiple-001.html Text transformation happens after [[#white-space-phase-1]] but before [[#white-space-phase-2]]. This means that ''full-width'' only transforms spaces (U+0020) to U+3000 IDEOGRAPHIC SPACE within [=preserved=] [=white space=]. text-transform/text-transform-fullwidth-006.html text-transform/text-transform-fullwidth-007.html text-transform/text-transform-fullwidth-008.html text-transform/text-transform-fullwidth-009.html Note: As defined in [[#order]], transforming text affects line-breaking and other formatting operations.

White Space and Wrapping: the 'white-space' property

	Name: white-space
	Value: normal | pre | nowrap | pre-wrap | break-spaces | pre-line
	Initial: normal
	Applies to: text
	Inherited: yes
	Canonical order: n/a
	Computed value: specified keyword
	Animation type: discrete
	
inheritance.html parsing/white-space-valid.html parsing/white-space-invalid.html parsing/white-space-computed.html white-space/ws-break-spaces-applies-to-001.html white-space/ws-break-spaces-applies-to-002.html white-space/ws-break-spaces-applies-to-003.html white-space/ws-break-spaces-applies-to-005.html white-space/ws-break-spaces-applies-to-006.html white-space/ws-break-spaces-applies-to-007.html white-space/ws-break-spaces-applies-to-008.html white-space/ws-break-spaces-applies-to-009.html white-space/ws-break-spaces-applies-to-010.html white-space/ws-break-spaces-applies-to-011.html white-space/ws-break-spaces-applies-to-012.html white-space/ws-break-spaces-applies-to-013.html white-space/ws-break-spaces-applies-to-014.html white-space/ws-break-spaces-applies-to-015.html white-space/white-space-applies-to-text-001.html white-space/white-space-pre-031.html white-space/white-space-pre-032.html white-space/white-space-pre-034.html white-space/white-space-pre-035.html c562-white-sp-000.xht white-space-006.xht white-space-007.xht white-space-applies-to-001.xht white-space-applies-to-002.xht white-space-applies-to-002.xht white-space-applies-to-003.xht white-space-applies-to-005.xht white-space-applies-to-006.xht white-space-applies-to-007.xht white-space-applies-to-008.xht white-space-applies-to-009.xht white-space-applies-to-010.xht white-space-applies-to-011.xht white-space-applies-to-012.xht white-space-applies-to-013.xht white-space-applies-to-014.xht white-space-applies-to-015.xht white-space-mixed-001.xht white-space-mixed-002.xht white-space-mixed-003.xht white-space-mixed-004.xht This property specifies two things: Values have the following meanings, which must be interpreted according to the [[#white-space-rules|White Space Processing]] and [[#line-breaking|Line Breaking]] rules:
normal
This value directs user agents to collapse sequences of [=white space=] into a single character (or [[#line-break-transform|in some cases]], no character). Lines may wrap at allowed [=soft wrap opportunities=], as determined by the line-breaking rules in effect, in order to minimize inline-axis overflow. white-space/white-space-normal-011.html white-space/white-space-pre-031.html white-space/white-space-wrap-after-nowrap-001.html line-break/line-break-anywhere-and-white-space-004.html line-break/line-break-anywhere-and-white-space-005.html white-space/white-space-applies-to-text-001.html white-space-normal-001.xht white-space-normal-002.xht white-space-normal-003.xht white-space-normal-004.xht white-space-normal-005.xht white-space-normal-006.xht white-space-normal-007.xht white-space-normal-008.xht white-space-normal-009.xht white-space-p-element-001.xht
pre
This value prevents user agents from collapsing sequences of [=white space=]. [=Segment breaks=] such as line feeds are preserved as [=forced line breaks=]. Lines only break at [=forced line breaks=]; content that does not fit within the block container overflows it. white-space-pre-001.xht white-space-pre-002.xht white-space-pre-005.xht white-space-pre-006.xht white-space-pre-007.xht white-space-pre-element-001.xht white-space/white-space-zero-fontsize-001.html white-space/white-space-zero-fontsize-002.html white-space/white-space-pre-031.html white-space/white-space-pre-032.html white-space/white-space-pre-034.html white-space/white-space-pre-035.html white-space/white-space-pre-011.html white-space/white-space-pre-051.html white-space/white-space-pre-052.html line-break/line-break-anywhere-and-white-space-001.html line-break/line-break-anywhere-and-white-space-003.html white-space/white-space-zero-fontsize-001.html white-space/white-space-zero-fontsize-002.html white-space/white-space-intrinsic-size-015.html white-space/white-space-intrinsic-size-016.html white-space/white-space-intrinsic-size-018.html white-space/pre-with-whitespace-crash.html word-break/break-boundary-2-chars-002.html white-space/white-space-applies-to-text-001.html
nowrap
Like ''white-space/normal'', this value collapses [=white space=]; but like ''pre'', it does not allow wrapping. white-space/white-space-nowrap-011.html white-space/white-space-wrap-after-nowrap-001.html line-break/line-break-anywhere-and-white-space-002.html overflow-wrap/overflow-wrap-anywhere-008.html white-space/nowrap-wbr-and-space-crash.html word-break/break-boundary-2-chars-002.html white-space/white-space-applies-to-text-001.html white-space-nowrap-001.xht white-space-nowrap-005.xht white-space-nowrap-006.xht text-align-white-space-004.xht text-align-white-space-008.xht white-space-nowrap-attribute-001.xht white-space-processing-006.xht
pre-wrap
Like ''pre'', this value preserves [=white space=]; but like ''white-space/normal'', it allows wrapping. white-space/pre-wrap-001.html white-space/pre-wrap-002.html white-space/pre-wrap-003.html white-space/pre-wrap-004.html white-space/pre-wrap-005.html white-space/pre-wrap-006.html white-space/pre-wrap-007.html white-space/pre-wrap-009.html white-space/pre-wrap-010.html white-space/pre-wrap-011.html white-space/pre-wrap-012.html white-space/pre-wrap-013.html white-space/pre-wrap-014.html white-space/pre-wrap-051.html white-space/pre-wrap-052.html white-space/textarea-pre-wrap-001.html white-space/textarea-pre-wrap-002.html white-space/textarea-pre-wrap-003.html white-space/textarea-pre-wrap-004.html white-space/textarea-pre-wrap-005.html white-space/textarea-pre-wrap-006.html white-space/textarea-pre-wrap-007.html white-space/textarea-pre-wrap-011.html white-space/textarea-pre-wrap-012.html white-space/textarea-pre-wrap-013.html white-space/textarea-pre-wrap-014.html white-space/white-space-pre-032.html white-space/pre-wrap-leading-spaces-001.html white-space/pre-wrap-leading-spaces-002.html white-space/pre-wrap-leading-spaces-003.html white-space/pre-wrap-leading-spaces-004.html white-space/pre-wrap-leading-spaces-005.html white-space/pre-wrap-leading-spaces-006.html white-space/pre-wrap-leading-spaces-007.html white-space/pre-wrap-leading-spaces-008.html white-space/pre-wrap-leading-spaces-009.html white-space/pre-wrap-leading-spaces-010.html white-space/pre-wrap-leading-spaces-011.html white-space/pre-wrap-leading-spaces-012.html white-space/pre-wrap-leading-spaces-013.html white-space/pre-wrap-leading-spaces-014.html white-space/pre-wrap-leading-spaces-015.html white-space/pre-wrap-leading-spaces-016.html white-space/pre-wrap-leading-spaces-017.html white-space/white-space-pre-wrap-trailing-spaces-001.html white-space/white-space-pre-wrap-trailing-spaces-002.html white-space/white-space-pre-wrap-trailing-spaces-003.html white-space/white-space-pre-wrap-trailing-spaces-004.html white-space/white-space-pre-wrap-trailing-spaces-005.html white-space/white-space-pre-wrap-trailing-spaces-006.html white-space/white-space-pre-wrap-trailing-spaces-007.html white-space/white-space-pre-wrap-trailing-spaces-008.html white-space/white-space-pre-wrap-trailing-spaces-010.html white-space/white-space-pre-wrap-trailing-spaces-011.html white-space/trailing-other-space-separators-002.html white-space/pre-wrap-tab-001.html white-space/pre-wrap-tab-002.html white-space/pre-wrap-tab-003.html white-space/pre-wrap-tab-004.html white-space/pre-wrap-tab-005.html white-space/pre-wrap-tab-006.html line-break/line-break-anywhere-and-white-space-006.html line-break/line-break-anywhere-and-white-space-007.html white-space/white-space-intrinsic-size-013.html white-space/white-space-intrinsic-size-014.html white-space/white-space-intrinsic-size-017.html white-space/white-space-applies-to-text-001.html
break-spaces
The behavior is identical to that of ''white-space/pre-wrap'', except that: Note: This value does not guarantee that there will never be any overflow due to white space: for example, if the line length is so short that even a single white space character does not fit, overflow is unavoidable.
pre-line
Like ''white-space/normal'', this value collapses consecutive [=white space characters=] and allows wrapping, but it preserves [=segment breaks=] in the source as [=forced line breaks=]. white-space-005.xht white-space-generated-content-before-001.xht white-space-processing-004.xht white-space-processing-007.xht white-space-processing-010.xht white-space-processing-017.xht white-space-processing-021.xht white-space-processing-024.xht white-space-processing-027.xht white-space-processing-028.xht white-space-processing-029.xht white-space-processing-030.xht white-space-processing-035.xht white-space-processing-036.xht white-space-processing-045.xht white-space-processing-053.xht text-align-white-space-002.xht text-align-white-space-006.xht white-space/pre-line-051.html white-space/pre-line-052.html white-space/white-space-pre-035.html white-space/white-space-intrinsic-size-019.html white-space/white-space-intrinsic-size-020.html white-space/pre-line-br-with-whitespace-child-crash.html white-space/pre-line-with-space-and-newline.html white-space/white-space-applies-to-text-001.html
[=White space=] that was not removed or collapsed due to white space processing is called preserved white space. Note: In some cases, [=preserved white space=] and [=other space separators=] can [=hang=] when at the end of the line; this can affect whether they are measured for [=intrinsic sizing=]. The following informative table summarizes the behavior of various 'white-space' values:
New Lines Spaces and Tabs Text Wrapping End-of-line [=spaces=] End-of-line [=other space separators=]
''white-space/normal'' Collapse Collapse Wrap Remove Hang
''pre'' Preserve Preserve No wrap Preserve No wrap
''white-space/nowrap'' Collapse Collapse No wrap Remove Hang
''pre-wrap'' Preserve Preserve Wrap Hang Hang
''break-spaces'' Preserve Preserve Wrap Wrap Wrap
''pre-line'' Preserve Collapse Wrap Remove Hang
white-space/trailing-space-and-text-alignment-002.html white-space/trailing-space-and-text-alignment-rtl-002.html See [[#white-space-processing|White Space Processing Rules]] for details on how [=white space=] collapses. See [[#line-breaking|Line Breaking]] for details on wrapping behavior.

White Space Processing & Control Characters

The source text of a document often contains formatting that is not relevant to the final rendering: for example, breaking the source into segments (lines) for ease of editing or adding [=white space characters=] such as [=tabs=] and [=spaces=] to indent the source code. CSS white space processing allows the author to control interpretation of such formatting: to preserve or collapse it away when rendering the document. White space processing in CSS (which is controlled with the 'white-space' property) interprets [=white space characters=] only for rendering: it has no effect on the underlying document data. Note: Depending on the document language, segments can be separated by a particular newline sequence (such as a line feed or CRLF pair), or delimited by some other mechanism, such as the SGML RECORD-START and RECORD-END tokens.

For CSS processing, each document language–defined “segment break” or “newline sequence”-- or if none are defined, each line feed (U+000A)-- in the text is treated as a segment break, which is then interpreted for rendering as specified by the 'white-space' property. In the case of HTML, [[html#newlines|newlines]] are [=normalize newlines|normalized=] to line feed characters (U+000A) for representation in the DOM, so when an HTML document is represented as a DOM tree each line feed (U+000A) is treated as a [=segment break=]. [[HTML]] [[DOM]] Note: In most common CSS implementations, HTML does not get styled directly. Instead, it is processed into a DOM tree, which is then styled. Unlike HTML, the DOM does not give any particular meaning to carriage returns (U+000D), so they are not treated as [=segment breaks=]. If carriage returns (U+000D) are inserted into the DOM by means other than HTML parsing, they then get treated as defined below. white-space-processing-005.xht white-space-processing-006.xht white-space-processing-007.xht Note: A document parser might not only normalize any [=segment breaks=], but also collapse other space characters or otherwise process white space according to markup rules. Because CSS processing occurs after the parsing stage, it is not possible to restore these characters for styling. Therefore, some of the behavior specified below can be affected by these limitations and may be user agent dependent. Note: Anonymous blocks consisting entirely of [=collapsible=] [=white space=] are removed from the rendering tree. Thus any such [=white space=] surrounding a block-level element is collapsed away. See [[CSS2/visuren#anonymous]]. [[CSS2]] Control characters ([=Unicode category=] Cc)-- other than tabs (U+0009), line feeds (U+000A), carriage returns (U+000D) and sequences that form a [=segment break=]-- must be rendered as a visible glyph which the UA must synthesize if the glyphs found in the font are not visible, and must be otherwise treated as any other character of the Other Symbols (So) [=general category=] and Common [=Unicode Script|script=]. The UA may use a glyph provided by a font specifically for the control character, substitute the glyphs provided for the corresponding symbol in the Control Pictures block, generate a visual representation of its code point value, or use some other method to provide an appropriate visible glyph. As required by Unicode, unsupported Default_ignorable characters must be ignored for text rendering. [[!UNICODE]] white-space/control-chars-000.html white-space/control-chars-001.html white-space/control-chars-002.html white-space/control-chars-003.html white-space/control-chars-004.html white-space/control-chars-005.html white-space/control-chars-006.html white-space/control-chars-007.html white-space/control-chars-008.html white-space/control-chars-00B.html white-space/control-chars-00C.html white-space/control-chars-00D.html white-space/control-chars-00E.html white-space/control-chars-00F.html white-space/control-chars-010.html white-space/control-chars-011.html white-space/control-chars-012.html white-space/control-chars-013.html white-space/control-chars-014.html white-space/control-chars-015.html white-space/control-chars-016.html white-space/control-chars-017.html white-space/control-chars-018.html white-space/control-chars-019.html white-space/control-chars-01A.html white-space/control-chars-01B.html white-space/control-chars-01C.html white-space/control-chars-01D.html white-space/control-chars-01E.html white-space/control-chars-01F.html white-space/control-chars-07F.html white-space/control-chars-080.html white-space/control-chars-081.html white-space/control-chars-082.html white-space/control-chars-083.html white-space/control-chars-084.html white-space/control-chars-085.html white-space/control-chars-086.html white-space/control-chars-087.html white-space/control-chars-088.html white-space/control-chars-089.html white-space/control-chars-08A.html white-space/control-chars-08B.html white-space/control-chars-08C.html white-space/control-chars-08D.html white-space/control-chars-08E.html white-space/control-chars-08F.html white-space/control-chars-090.html white-space/control-chars-091.html white-space/control-chars-092.html white-space/control-chars-093.html white-space/control-chars-094.html white-space/control-chars-095.html white-space/control-chars-096.html white-space/control-chars-097.html white-space/control-chars-098.html white-space/control-chars-099.html white-space/control-chars-09A.html white-space/control-chars-09B.html white-space/control-chars-09C.html white-space/control-chars-09D.html white-space/control-chars-09E.html white-space/control-chars-09F.html control-characters-001.html control-characters-002.xht white-space-control-characters-001.xht Carriage returns (U+000D) are treated identically to spaces (U+0020) in all respects. white-space/control-chars-00D.html white-space-processing-005.xht white-space-processing-006.xht white-space-processing-007.xht Note: For HTML documents, carriage returns present in the source code are converted to line feeds at the parsing stage (see [[HTML#preprocessing-the-input-stream]] and the definition of [=normalize newlines=] in Infra and therefore do no appear as U+000D CARRIAGE RETURN to CSS. [[HTML]] [[INFRA]]) However, the character is preserved-- and the above rule observable-- when encoded using an escape sequence (&#x0d;).

The White Space Processing Rules

Except where specified otherwise, white space processing in CSS affects only the document white space characters: spaces (U+0020), tabs (U+0009), and [[#white-space-processing|segment breaks]]. white-space-normal-003.xht white-space-normal-004.xht white-space-normal-005.xht white-space-normal-006.xht white-space-normal-007.xht white-space-normal-008.xht white-space-nowrap-005.xht white-space-nowrap-006.xht white-space-pre-005.xht white-space-pre-006.xht white-space-processing-054.xht white-space-processing-055.xht white-space-processing-056.xht white-space/display-contents-remove-whitespace-change.html white-space/remove-slotted-with-whitespace-sibling.html Note: The set of characters considered [=document white space=] (part of the document content) and those considered syntactic white space (part of the CSS syntax) are not necessarily identical. However, since both include spaces (U+0020), tabs (U+0009), and line feeds (U+000A) most authors won’t notice any differences. Besides space (U+0020) and no-break space (U+00A0), Unicode defines a number of additional space separator characters. [[UNICODE]] In this specification all characters in the Unicode [=general category=] Zs except space (U+0020) and no-break space (U+00A0) are collectively referred to as other space separators. white-space/trailing-other-space-separators-001.html white-space/trailing-other-space-separators-002.html white-space/trailing-other-space-separators-003.html white-space/trailing-other-space-separators-004.html white-space/trailing-other-space-separators-break-spaces-001.html white-space/trailing-other-space-separators-break-spaces-002.html white-space/trailing-other-space-separators-break-spaces-003.html white-space/trailing-other-space-separators-break-spaces-004.html white-space/trailing-other-space-separators-break-spaces-005.html white-space/trailing-other-space-separators-break-spaces-006.html white-space/trailing-other-space-separators-break-spaces-007.html white-space/trailing-other-space-separators-break-spaces-008.html white-space/trailing-other-space-separators-break-spaces-009.html white-space/trailing-other-space-separators-break-spaces-010.html white-space/trailing-other-space-separators-break-spaces-011.html white-space/trailing-other-space-separators-break-spaces-012.html white-space/trailing-other-space-separators-break-spaces-013.html white-space/trailing-other-space-separators-break-spaces-014.html white-space/trailing-other-space-separators-break-spaces-015.html

Phase I: Collapsing and Transformation

For each inline (including anonymous inlines; see [[CSS2/visuren#anonymous]] [[CSS2]]) within an [=inline formatting context=], [=white space characters=] are processed as follows prior to [=line breaking=] and [[css-writing-modes-4#text-direction|bidi reordering]], ignoring bidi formatting characters (characters with the Bidi_Control property [[!UAX9]]) as if they were not there: white-space/white-space-collapse-002.html white-space/white-space-normal-011.html white-space/white-space-nowrap-011.html bidi-text/bidi-002.xht bidi-text/bidi-004.xht bidi-text/line-breaking-bidi-001.xht bidi-text/line-breaking-bidi-002.xht bidi-text/line-breaking-bidi-003.xht white-space-collapsing-bidi-001.xht white-space-collapsing-bidi-002.xht
The following example illustrates the interaction of white-space collapsing and bidirectionality. Consider the following markup fragment, taking special note of [=spaces=] (with varied backgrounds and borders for emphasis and identification):
<ltr>A <rtl> B </rtl> C</ltr>
where the <ltr> element represents a left-to-right embedding and the <rtl> element represents a right-to-left embedding. If the 'white-space' property is set to ''white-space/normal'', the white-space processing model will result in the following: This will leave two [=spaces=], one after the A in the left-to-right embedding level, and one after the B in the right-to-left embedding level. The text will then be ordered according to the Unicode bidirectional algorithm, with the end result being:
A  BC
Note that there will be two [=spaces=] between A and B, and none between B and C. This is best avoided by putting [=spaces=] outside the element instead of just inside the opening and closing tags and, where practical, by relying on implicit bidirectionality instead of explicit embedding levels.
white-space-bidirectionality-001.xht

Phase II: Trimming and Positioning

Then, the entire block is rendered. Inlines are laid out, taking [[css-writing-modes-4#text-direction|bidi reordering]] into account, and [=wrapping=] as specified by the 'white-space' property. As each line is laid out,
  1. A sequence of [=collapsible=] [=spaces=] at the beginning of a line is removed. white-space/line-edge-white-space-collapse-002.html white-space/break-spaces-051.html white-space/break-spaces-052.html white-space/pre-line-051.html white-space/pre-line-052.html white-space/pre-wrap-051.html white-space/pre-wrap-052.html white-space/white-space-pre-051.html white-space/white-space-pre-052.html white-space/full-width-leading-spaces-001.html white-space/full-width-leading-spaces-002.html white-space/full-width-leading-spaces-003.html white-space-collapsing-003.xht white-space-collapsing-bidi-003.xht white-space-normal-001.xht white-space-normal-002.xht white-space-processing-037.xht white-space-processing-038.xht white-space-processing-039.xht white-space-processing-040.xht white-space-processing-041.xht
  2. If the [=tab size=] is zero, [=preserved=] [=tabs=] are not rendered. Otherwise, each [=preserved=] [=tab=] is rendered as a horizontal shift that lines up the start edge of the next glyph with the next [=tab stop=]. If this distance is less than ''0.5ch'', then the subsequent [=tab stop=] is used instead. Tab stops occur at points that are multiples of the [=tab size=] from the starting content edge of the [=preserved=] [=tab=]’s nearest [=block container=] ancestor. The [=tab size=] is given by the 'tab-size' property. white-space/tab-stop-threshold-001.html white-space/tab-stop-threshold-002.html white-space/tab-stop-threshold-003.html white-space/tab-stop-threshold-004.html white-space/tab-stop-threshold-005.html white-space/tab-stop-threshold-006.html white-space/white-space-pre-011.html tab-size/tab-min-rendered-width-1.html tab-size/tab-size-integer-003.html text-indent/text-indent-tab-positions-001.html tab-size/tab-size-inline-002.html white-space-processing-042.xht Note: See the Unicode rules on how tabulation (U+0009) interacts with bidi. [[UAX9]] bidi/bidi-tab-001.html white-space/tab-bidi-001.html
  3. A sequence of [=collapsible=] [=spaces=] at the end of a line is removed, as well as any trailing U+1680   OGHAM SPACE MARK whose 'white-space' property is ''white-space/normal'', ''white-space/nowrap'', or ''pre-line''. white-space/line-edge-white-space-collapse-001.html white-space/pre-float-001.html white-space/pre-wrap-float-001.html white-space/trailing-space-before-br-001.html white-space/trailing-ogham-001.html white-space/trailing-ogham-002.html white-space/trailing-ogham-003.html overflow-wrap/overflow-wrap-anywhere-011.html white-space-collapsing-003.xht white-space-collapsing-bidi-003.xht white-space-normal-001.xht white-space-normal-002.xht white-space-processing-005.xht white-space-processing-043.xht white-space-processing-044.xht white-space-processing-045.xht white-space-processing-046.xht white-space-processing-047.xht Note: Due to Unicode Bidirectional Algorithm rule L1, a sequence of [=collapsible=] [=spaces=] located at the end of the line prior to [[css-writing-modes-4#text-direction|bidi reordering]] will also be at the end of the line after reordering. [[UAX9]] [[CSS-WRITING-MODES-4]] white-space/eol-spaces-bidi-001.html white-space/eol-spaces-bidi-003.html white-space/trailing-space-rtl-001.html
  4. If there remains any sequence of [=white space=], [=other space separators=], and/or [=preserved=] [=tabs=] at the end of a line (after [[css-writing-modes-4#text-direction|bidi reordering]] [[CSS-WRITING-MODES-4]]):
This example shows that [=conditionally hanging=] white space at the end of lines with forced breaks provides symmetry with the start of the line. An underline is added to help visualize the spaces.

			p {
				white-space: pre-wrap;
				width: 5ch;
				border: solid 1px;
				font-family: monospace;
				text-align: center;
			}
		
<p> 0 </p> The sample above would be rendered as follows:
0
Since the final [=space=] is before a forced line break and does not overflow, it does not hang, and centering works as expected.
This example illustrates the difference between [=hanging=] [=spaces=] at the end of lines without forced breaks, and [=conditionally hanging=] them at the end of lines with forced breaks. An underline is added to help visualize the [=spaces=].

			p {
				white-space: pre-wrap;
				width: 3ch;
				border: solid 1px;
				font-family: monospace;
			}
		
<p> 0 0 0 0 </p> The sample above would be rendered as follows:
0
0 0
0
If p { text-align: right; } was added, the result would be as follows:
0
0 0
0
As the [=preserved=] [=spaces=] at the end of lines without a forced break must [=hang=], they are not considered when placing the rest of the line during text alignment. When aligning towards the end, this means any such [=spaces=] will overflow, and will not prevent the rest of the line’s content from being flush with the edge of the line. On the other hand, preserved spaces at the end of a line with a forced break [=conditionally hang=]. Since the space at the end of the last line would not overflow in this example, it does not [=hang=] and therefore is considered during text alignment.
In the following example, there is not enough room on any line to fit the end-of-line spaces, so they [=hang=] on all lines: the one on the line without a forced break because it must, as well as the one on the line with a forced break, because it [=conditionally hangs=] and overflows. An underline is added to help visualize the spaces.

			p {
				white-space: pre-wrap;
				width: 3ch;
				border: solid 1px;
				font-family: monospace;
			}
		
<p>0 0 0 0 </p>
0 0
0 0
The last line is not wrapped before the last 0 because characters that [=conditionally hang=] are not considered when measuring the line’s contents for fit.

Segment Break Transformation Rules

When 'white-space' is ''pre'', ''pre-wrap'', ''break-spaces'', or ''pre-line'', [=segment breaks=] are not [=collapsible=] and are instead transformed into a preserved line feed (U+000A). white-space-008.xht white-space-processing-016.xht white-space-processing-017.xht white-space-processing-018.xht For other values of 'white-space', [=segment breaks=] are [=collapsible=], and are collapsed as follows:
  1. First, any collapsible [=segment break=] immediately following another collapsible [=segment break=] is removed. line-breaking/segment-break-transformation-unremovable-2.html line-breaking/segment-break-transformation-unremovable-4.html
  2. Then any remaining [=segment break=] is either transformed into a space (U+0020) or removed depending on the context before and after the break. The rules for this operation are UA-defined in this level. line-breaking/segment-break-transformation-unremovable-1.html line-breaking/segment-break-transformation-unremovable-2.html line-breaking/segment-break-transformation-unremovable-3.html line-breaking/segment-break-transformation-unremovable-4.html Note: The white space processing rules have already removed any [=tabs=] and [=spaces=] around the [=segment break=] before this context is evaluated.
The purpose of the segment break transformation rules (and white space collapsing in general) is to “unbreak” text that has been [[#white-space-processing|broken into segments]] to make the document source code easier to work with. In languages that use word separators, such as English and Korean, “unbreaking” a line requires joining the two lines with a [=space=].
				Here is an English paragraph
				that is broken into multiple lines
				in the source code so that it can
				be more easily read and edited
				in a text editor.
			
Here is an English paragraph that is broken into multiple lines in the source code so that it can be more easily read and edited in a text editor.
Eliminating a line break in English requires maintaining a [=space=] in its place.
In languages that have no word separators, such as Chinese, “unbreaking” a line requires joining the two lines with no intervening space.
				這個段落是那麼長,
				在一行寫不行。最好
				用三行寫。
			

這個段落是那麼長,在一行寫不行。最好用三行寫。

Eliminating a line break in Chinese requires eliminating any intervening [=white space=].
The segment break transformation rules can use adjacent context to either transform the segment break into a space or eliminate it entirely.
Note: Historically, HTML and CSS have unconditionally converted [=segment breaks=] to spaces, which has prevented content authored in languages such as Chinese from being able to break lines within the source. Thus UA heuristics need to be conservative about where they discard [=segment breaks=] even as they strive to improve support for such languages.

Tab Character Size: the 'tab-size' property

	Name: tab-size
	Value: <> | <>
	Initial: 8
	Applies to: text
	Inherited: yes
	Computed value: the specified number or absolute length
	Animation type: by computed value type
	Canonical order: n/a
	
tab-size/tab-size-integer-001.html tab-size/tab-size.html tab-size/tab-size-inheritance-001.html inheritance.html parsing/tab-size-valid.html parsing/tab-size-invalid.html parsing/tab-size-computed.html tab-size/tab-size-computed-value-001.html tab-size/tab-size-inline-001.html animations/tab-size-interpolation.html This property determines the tab size used to render [=preserved=] tab characters (U+0009). A <> represents the measure as a multiple of the advance width of the space character (U+0020) of the nearest [=block container=] ancestor of the [=preserved=] [=tab=], including its associated 'letter-spacing' and 'word-spacing'. Negative values are not allowed. tab-size/tab-size-integer-001.html tab-size/tab-size-integer-002.html tab-size/tab-size-integer-003.html tab-size/tab-size-integer-004.html tab-size/tab-size-integer-005.html tab-size/tab-size-length-001.html tab-size/tab-size-length-002.html tab-size/tab-size-percent-001.html tab-size/tab-min-rendered-width-1.html tab-size/tab-size-spacing-001.html tab-size/tab-size-spacing-002.html tab-size/tab-size-spacing-003.html white-space/tab-stop-threshold-001.html white-space/tab-stop-threshold-002.html white-space/tab-stop-threshold-003.html white-space/tab-stop-threshold-004.html white-space/tab-stop-threshold-005.html white-space/tab-stop-threshold-006.html text-indent/text-indent-tab-positions-001.html tab-size/tab-size-block-ancestor.html white-space/white-space-zero-fontsize-002.html white-space-processing-042.xht

Line Breaking and Word Boundaries

When inline-level content is laid out into lines, it is broken across line boxes. Such a break is called a line break. When a line is broken due to explicit line-breaking controls (such as a preserved newline character), or due to the start or end of a block, it is a forced line break. When a line is broken due to content wrapping (i.e. when the UA creates unforced line breaks in order to fit the content within the measure), it is a soft wrap break. The process of breaking inline-level content into lines is called line breaking. Wrapping is only performed at an allowed break point, called a soft wrap opportunity. When wrapping is enabled (see 'white-space'), the UA must minimize the amount of content overflowing a line by wrapping the line at a [=soft wrap opportunity=], if one exists. line-breaking/line-breaking-020.html In most writing systems, in the absence of hyphenation a [=soft wrap opportunity=] occurs only at word boundaries. Many such systems use [=spaces=] or punctuation to explicitly separate words, and [=soft wrap opportunities=] can be identified by these characters. Scripts such as Thai, Lao, and Khmer, however, do not use spaces or punctuation to separate words. Although the zero width space (U+200B) can be used as an explicit word delimiter in these scripts, this practice is not common. As a result, a lexical resource is needed to correctly identify [=soft wrap opportunities=] in such texts. In some other writing systems, [=soft wrap opportunities=] are based on orthographic syllable boundaries, not word boundaries. Some of these systems, such as Javanese and Balinese, are similar to Thai and Lao in that they require analysis of the text to find breaking opportunities. In others such as Chinese (as well as Japanese, Yi, and sometimes also Korean), each syllable tends to correspond to a single [=typographic letter unit=], and thus line breaking conventions allow the line to break anywhere except between certain character combinations. Additionally the level of strictness in these restrictions varies with the typesetting style. line-breaking/line-breaking-023.html line-breaking/line-breaking-024.html line-breaking/line-breaking-025.html line-breaking/line-breaking-026.html line-breaking/line-breaking-027.html i18n/css3-text-line-break-baspglwj-003.html i18n/css3-text-line-break-baspglwj-004.html i18n/css3-text-line-break-baspglwj-005.html i18n/css3-text-line-break-baspglwj-006.html i18n/css3-text-line-break-baspglwj-007.html i18n/css3-text-line-break-baspglwj-008.html i18n/css3-text-line-break-baspglwj-009.html i18n/css3-text-line-break-baspglwj-010.html i18n/css3-text-line-break-baspglwj-011.html i18n/css3-text-line-break-baspglwj-012.html i18n/css3-text-line-break-baspglwj-014.html i18n/css3-text-line-break-baspglwj-015.html i18n/css3-text-line-break-baspglwj-016.html i18n/css3-text-line-break-baspglwj-017.html i18n/css3-text-line-break-baspglwj-018.html i18n/css3-text-line-break-baspglwj-019.html 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word-break/word-break-normal-ja-002.html word-break/word-break-normal-ja-004.html word-break/word-break-normal-km-000.html word-break/word-break-normal-ko-000.html word-break/word-break-normal-lo-000.html word-break/word-break-normal-my-000.html word-break/word-break-normal-tdd-000.html word-break/word-break-normal-th-000.html word-break/word-break-normal-th-001.html word-break/word-break-normal-zh-000.html While CSS does not fully define where [=soft wrap opportunities=] occur, some controls are provided to distinguish common variations: Note: Unicode Standard Annex #14: Unicode Line Breaking Algorithm defines a baseline behavior for line breaking for all scripts in Unicode, which is expected to be further tailored. [[UAX14]] More information on line breaking conventions can be found in Requirements for Japanese Text Layout [[JLREQ]] and Formatting Rules for Japanese Documents [[JIS4051]] for Japanese, Requirements for Chinese Text Layout [[CLREQ]] and General Rules for Punctuation [[ZHMARK]] for Chinese. See also the Internationalization Working Group’s Language Enablement Index which includes more information on additional languages. [[TYPOGRAPHY]] Any guidance on additional appropriate references would be much appreciated. shaping/shaping_lig-001.html

Line Breaking Details

When determining [=line breaks=]:

Breaking Rules for Letters: the 'word-break' property

	Name: word-break
	Value: normal | keep-all | break-all | break-word
	Initial: normal
	Applies to: text
	Inherited: yes
	Canonical order: n/a
	Computed value: specified keyword
	Animation type: discrete
	
inheritance.html parsing/word-break-invalid.html parsing/word-break-valid.html parsing/word-break-computed.html word-break/word-break-break-all-inline-001.html word-break/word-break-break-all-inline-002.html word-break/word-break-break-all-inline-003.html word-break/word-break-break-all-inline-004.tentative.html word-break/word-break-break-all-inline-005.html word-break/word-break-break-all-inline-006.html word-break/word-break-break-all-inline-007.tentative.html word-break/word-break-break-all-inline-009.html word-break/word-break-break-all-062.html word-break/word-break-keep-all-063.html This property specifies [=soft wrap opportunities=] between letters, i.e. where it is “normal” and permissible to break lines of text. Specifically it controls whether a [=soft wrap opportunity=] generally exists between adjacent [=typographic letter units=], treating non-[=letter=] [=typographic character units=] belonging to the NU, AL, AI, or ID Unicode line breaking classes as [=typographic letter units=] for this purpose (only). [[!UAX14]] It does not affect rules governing the [=soft wrap opportunities=] created by [=white space=] (as well as by [=other space separators=]) and around punctuation. (See 'line-break' for controls affecting punctuation and small kana.) word-break/word-break-keep-all-005.html word-break/word-break-keep-all-006.html word-break/word-break-keep-all-007.html word-break/word-break-keep-all-008.html word-break/word-break-min-content-003.html
For example, in some styles of CJK typesetting, English words are allowed to break between any two letters, rather than only at spaces or hyphenation points; this can be enabled with ''word-break:break-all''.
A snippet of Japanese text with English in it.
			          The word 'caption' is broken into 'capt' and 'ion' across two lines.
An example of English text embedded in Japanese being broken at an arbitrary point in the word.
As another example, Korean has two styles of line-breaking: between any two Korean syllables (''word-break: normal'') or, like English, mainly at spaces (''word-break: keep-all'').
			각 줄의 마지막에 한글이 올 때 줄 나눔 기
			준을 “글자” 또는 “어절” 단위로 한다.
		
			각 줄의 마지막에 한글이 올 때 줄 나눔
			기준을 “글자” 또는 “어절” 단위로 한다.
		
Ethiopic similarly has two styles of line-breaking, either only breaking at [=word separators=] (''word-break: normal''), or also allowing breaks between letters within a word (''word-break: break-all'').
			ተወልዱ፡ኵሉ፡ሰብእ፡ግዑዛን፡ወዕሩያን፡
			በማዕረግ፡ወብሕግ።ቦሙ፡ኅሊና፡ወዐቅል፡
			ወይትጌበሩ፡አሐዱ፡ምስለ፡አሀዱ፡
			በመንፈሰ፡እኍና።
		
			ተወልዱ፡ኵሉ፡ሰብእ፡ግዑዛን፡ወዕሩያን፡በማ
			ዕረግ፡ወብሕግ።ቦሙ፡ኅሊና፡ወዐቅል፡ወይትጌ
			በሩ፡አሐዱ፡ምስለ፡አሀዱ፡በመንፈሰ፡እኍና።
		
Note: To enable additional break opportunities only in the case of overflow, see 'overflow-wrap'. Values have the following meanings:
normal
Words break according to their customary rules, as described [[#line-breaking|above]]. Korean, which commonly exhibits two different behaviors, allows breaks between any two consecutive Hangul/Hanja. For Ethiopic, which also exhibits two different behaviors, such breaks within words are not allowed. word-break/word-break-normal-001.html word-break/word-break-normal-002.html word-break/word-break-normal-003.html word-break/word-break-normal-ar-000.html word-break/word-break-normal-bo-000.html word-break/word-break-normal-en-000.html word-break/word-break-normal-hi-000.html word-break/word-break-normal-ja-000.html word-break/word-break-normal-ja-001.html word-break/word-break-normal-ja-002.html word-break/word-break-normal-ja-004.html word-break/word-break-normal-km-000.html word-break/word-break-normal-ko-000.html word-break/word-break-normal-lo-000.html word-break/word-break-normal-my-000.html word-break/word-break-normal-tdd-000.html word-break/word-break-normal-th-000.html word-break/word-break-normal-th-001.html word-break/word-break-normal-zh-000.html word-break/word-break-normal-ethiopic.html
break-all
Breaking is allowed within “words”: specifically, in addition to [=soft wrap opportunities=] allowed for ''word-break/normal'', any [=typographic letter units=] (and any [=typographic character units=] resolving to the NU (“numeric”), AL (“alphabetic”), or SA (“Southeast Asian”) line breaking classes [[!UAX14]]) are instead treated as ID (“ideographic characters”) for the purpose of line-breaking. Hyphenation is not applied. line-break/line-break-loose-hyphens-002.html line-break/line-break-normal-hyphens-002.html line-break/line-break-strict-hyphens-002.html overflow-wrap/overflow-wrap-anywhere-006.html white-space/break-spaces-006.html white-space/break-spaces-008.html white-space/break-spaces-before-first-char-004.html white-space/break-spaces-before-first-char-005.html white-space/break-spaces-before-first-char-006.html white-space/break-spaces-before-first-ideographic-char-004.html white-space/break-spaces-before-first-ideographic-char-005.html white-space/break-spaces-before-first-ideographic-char-006.html word-break/break-boundary-2-chars-002.html word-break/word-break-break-all-000.html word-break/word-break-break-all-001.html word-break/word-break-break-all-002.html word-break/word-break-break-all-003.html word-break/word-break-break-all-005.html word-break/word-break-break-all-006.html word-break/word-break-break-all-010.html word-break/word-break-break-all-012.html word-break/word-break-break-all-013.html word-break/word-break-break-all-014.html word-break/word-break-break-all-015.html word-break/word-break-break-all-016.html word-break/word-break-break-all-017.html word-break/word-break-break-all-018.html word-break/word-break-break-all-019.html word-break/word-break-break-all-020.html word-break/word-break-break-all-021.html word-break/word-break-break-all-022.html word-break/word-break-break-all-023.html word-break/word-break-break-all-024.html word-break/word-break-break-all-025.html word-break/word-break-break-all-026.html word-break/word-break-break-all-027.html word-break/word-break-break-all-028.html word-break/word-break-break-all-029.html word-break/word-break-break-all-030.html word-break/word-break-break-all-031.html word-break/word-break-break-all-032.html word-break/word-break-break-all-ethiopic.html word-break/word-break-break-all-inline-001.html word-break/word-break-break-all-inline-002.html word-break/word-break-break-all-inline-003.html word-break/word-break-break-all-inline-004.tentative.html word-break/word-break-break-all-inline-005.html word-break/word-break-break-all-inline-006.html word-break/word-break-break-all-inline-007.tentative.html word-break/word-break-break-all-inline-008.html word-break/word-break-break-all-inline-009.html word-break/word-break-break-all-inline-010.tentative.html Note: This value does not affect whether there are [=soft wrap opportunities=] around punctuation characters. To allow breaks anywhere, see ''line-break: anywhere''. white-space/break-spaces-before-first-char-011.html white-space/break-spaces-before-first-ideographic-char-011.html word-break/word-break-break-all-ethiopic.html Note: This option enables the other common behavior for Ethiopic. It is also often used in a context where the text consists predominantly of CJK characters with only short non-CJK excerpts, and it is desired that the text be better distributed on each line.
keep-all
Breaking is forbidden within “words”: implicit [=soft wrap opportunities=] between [=typographic letter units=] (or other [=typographic character units=] belonging to the NU, AL, AI, or ID Unicode line breaking classes [[!UAX14]]) are suppressed, i.e. breaks are prohibited between pairs of such characters (regardless of 'line-break' settings other than ''line-break/anywhere'') except where opportunities exist due to dictionary-based breaking. Otherwise this option is equivalent to ''word-break/normal''. In this style, sequences of CJK characters do not break. word-break/word-break-keep-all-000.html word-break/word-break-keep-all-001.html word-break/word-break-keep-all-002.html word-break/word-break-keep-all-003.html word-break/word-break-keep-all-009.html word-break/word-break-keep-all-010.html Note: This is the other common behavior for Korean (which uses [=spaces=] between words), and is also useful for mixed-script text where CJK snippets are mixed into another language that uses [=spaces=] for separation.
Symbols that line-break the same way as letters of a particular category are affected the same way as those letters.
Here’s a mixed-script sample text:
			这是一些汉字 and some Latin و کمی خط عربی และตัวอย่างการเขียนภาษาไทย በጽሑፍ፡ማራዘሙን፡አንዳንድ፡
		
The break-points are determined as follows (indicated by ‘·’):
''word-break: normal''
					这·是·一·些·汉·字·and·some·Latin·و·کمی·خط·عربی·และ·ตัวอย่าง·การเขียน·ภาษาไทย·በጽሑፍ፡·ማራዘሙን፡·አንዳንድ፡
				
''word-break: break-all''
					这·是·一·些·汉·字·a·n·d·s·o·m·e·L·a·t·i·n·و·ﮐ·ﻤ·ﻰ·ﺧ·ﻁ·ﻋ·ﺮ·ﺑ·ﻰ·แ·ล·ะ·ตั·ว·อ·ย่·า·ง·ก·า·ร·เ·ขี·ย·น·ภ·า·ษ·า·ไ·ท·ย·በ·ጽ·ሑ·ፍ፡·ማ·ራ·ዘ·ሙ·ን፡·አ·ን·ዳ·ን·ድ፡
				
''word-break: keep-all''
					这是一些汉字·and·some·Latin·و·کمی·خط·عربی·และ·ตัวอย่าง·การเขียน·ภาษาไทย·በጽሑፍ፡·ማራዘሙን፡·አንዳንድ፡
				
Japanese is usually typeset allowing line breaks within words. However, it is sometimes preferred to suppress these wrapping opportunities and to only allow wrapping at the end of certain sentence fragments. This is most commonly done in very short pieces of text, such as headings and table or figure captions. This can be achieved by marking the allowed wrapping points with <{wbr}> or U+200B ZERO WIDTH SPACE, and suppressing the other ones using ''word-break: keep-all''. For instance, the following markup can produce either of the renderings below, depending on the value of the 'word-break' property: <h1>窓ぎわの<wbr>トットちゃん</h1>
h1 { word-break: normal } h1 { word-break: keep-all }
Expected rendering
							窓ぎわのトットちゃ
							ん
						
							窓ぎわの
							トットちゃん
						
Result in your browser 窓ぎわのトットちゃん 窓ぎわのトットちゃん
When shaping scripts such as Arabic are allowed to break within words due to ''word-break/break-all'' the characters must still be shaped as if the word were [[#word-break-shaping|not broken]] (see [[#word-break-shaping]]). word-break/word-break-break-all-004.html For compatibility with legacy content, the 'word-break' property also supports a deprecated break-word keyword. When specified, this has the same effect as ''word-break: normal'' and ''overflow-wrap: anywhere'', regardless of the actual value of the 'overflow-wrap' property. white-space/pre-wrap-008.html white-space/pre-wrap-016.html word-break/word-break-break-word-overflow-wrap-interactions.html word-break/word-break-break-word-crash-001.html white-space/break-spaces-003.html white-space/break-spaces-004.html white-space/break-spaces-008.html white-space/break-spaces-before-first-char-010.html white-space/break-spaces-before-first-ideographic-char-010.html word-break/word-break-min-content-001.html word-break/word-break-min-content-002.html word-break/word-break-min-content-003.html word-break/word-break-min-content-004.html word-break/word-break-min-content-005.html word-break/word-break-min-content-006.html white-space/break-spaces-with-ideographic-space-002.html white-space/break-spaces-with-ideographic-space-004.html white-space/break-spaces-with-ideographic-space-006.html white-space/break-spaces-with-ideographic-space-008.html white-space/break-spaces-with-ideographic-space-009.html word-break/word-break-min-content-007.html

Line Breaking Strictness: the 'line-break' property

	Name: line-break
	Value: auto | loose | normal | strict | anywhere
	Initial: auto
	Applies to: text
	Inherited: yes
	Canonical order: n/a
	Computed value: specified keyword
	Animation type: discrete
	
inheritance.html parsing/line-break-valid.html parsing/line-break-invalid.html parsing/line-break-computed.html animations/line-break-no-interpolation.html This property specifies the strictness of line-breaking rules applied within an element: especially how [=wrapping=] interacts with punctuation and symbols. Values have the following meanings:
auto
The UA determines the set of line-breaking restrictions to use, and it may vary the restrictions based on the length of the line; e.g., use a less restrictive set of line-break rules for short lines.
loose
Breaks text using the least restrictive set of line-breaking rules. Typically used for short lines, such as in newspapers.
normal
Breaks text using the most common set of line-breaking rules.
strict
Breaks text using the most stringent set of line-breaking rules.
anywhere
There is a [=soft wrap opportunity=] around every [=typographic character unit=], including around any punctuation character or [=preserved white spaces=], or in the middle of words, disregarding any prohibition against line breaks, even those introduced by characters with the GL, WJ, or ZWJ line breaking classes or mandated by the 'word-break' property. [[UAX14]] The different wrapping opportunities must not be prioritized. Hyphenation is not applied. line-break/line-break-anywhere-001.html line-break/line-break-anywhere-002.html line-break/line-break-anywhere-003.html line-break/line-break-anywhere-004.html line-break/line-break-anywhere-005.html line-break/line-break-anywhere-006.html line-break/line-break-anywhere-007.html line-break/line-break-anywhere-008.html line-break/line-break-anywhere-009.html line-break/line-break-anywhere-010.html line-break/line-break-anywhere-011.html line-break/line-break-anywhere-012.html line-break/line-break-anywhere-013.html line-break/line-break-anywhere-014.html line-break/line-break-anywhere-015.html line-break/line-break-anywhere-016.html line-break/line-break-anywhere-017.html line-break/line-break-anywhere-and-white-space-001.html line-break/line-break-anywhere-and-white-space-002.html line-break/line-break-anywhere-and-white-space-003.html line-break/line-break-anywhere-and-white-space-004.html line-break/line-break-anywhere-and-white-space-005.html line-break/line-break-anywhere-and-white-space-006.html line-break/line-break-anywhere-and-white-space-007.html line-break/line-break-anywhere-and-white-space-008.html line-break/line-break-anywhere-and-white-space-009.html line-break/line-break-anywhere-and-white-space-009.html line-break/line-break-anywhere-overrides-uax-behavior-001.html line-break/line-break-anywhere-overrides-uax-behavior-002.html line-break/line-break-anywhere-overrides-uax-behavior-003.html line-break/line-break-anywhere-overrides-uax-behavior-004.html line-break/line-break-anywhere-overrides-uax-behavior-005.html line-break/line-break-anywhere-overrides-uax-behavior-006.html line-break/line-break-anywhere-overrides-uax-behavior-007.html line-break/line-break-anywhere-overrides-uax-behavior-008.html line-break/line-break-anywhere-overrides-uax-behavior-009.html line-break/line-break-anywhere-overrides-uax-behavior-010.html line-break/line-break-anywhere-overrides-uax-behavior-011.html line-break/line-break-anywhere-overrides-uax-behavior-012.html line-break/line-break-anywhere-overrides-uax-behavior-013.html line-break/line-break-anywhere-overrides-uax-behavior-014.html line-break/line-break-anywhere-overrides-uax-behavior-015.html line-break/line-break-anywhere-overrides-uax-behavior-016.html line-break/line-break-shaping-001.html white-space/break-spaces-before-first-char-007.html white-space/break-spaces-before-first-char-011.html white-space/break-spaces-before-first-ideographic-char-007.html white-space/break-spaces-before-first-ideographic-char-011.html Note: This value triggers the line breaking rules typically seen in terminals.
Note: ''line-break/anywhere'' only allows [=preserved white spaces=] at the end of the line to be wrapped to the next line when 'white-space' is set to ''white-space/break-spaces'', because in other cases:
  • [=preserved white space=] at the end/start of the line is discarded (''white-space/normal'', ''white-space/pre-line'')
  • wrapping is forbidden altogether (''white-space/nowrap'', ''pre'')
  • the [=preserved white space=] [=hang=] (''pre-wrap'').
When it does have an effect on [=preserved white space=], with ''white-space: break-spaces'', it allows breaking before the first space of a sequence, which ''break-spaces'' on its own does not.
line-break/line-break-anywhere-005.html white-space/break-spaces-before-first-char-007.html white-space/break-spaces-before-first-char-008.html white-space/break-spaces-before-first-char-009.html white-space/break-spaces-before-first-char-010.html white-space/break-spaces-before-first-ideographic-char-007.html white-space/break-spaces-before-first-ideographic-char-008.html white-space/break-spaces-before-first-ideographic-char-009.html white-space/break-spaces-before-first-ideographic-char-010.html
CSS distinguishes between four levels of strictness in the rules for text wrapping. The precise set of rules in effect for each of ''line-break/loose'', ''line-break/normal'', and ''line-break/strict'' is up to the UA and should follow language conventions. However, this specification does require that: Note: The requirements listed above only create distinctions in CJK text. In an implementation that matches only the rules above, and no additional rules, 'line-break' would only affect CJK code points unless the writing system is tagged as Chinese or Japanese. Future levels may add additional specific rules for other writing systems and languages as their requirements become known.
As UAs can add additional distinctions between ''line-break/strict''/''line-break/normal''/''line-break/loose'' modes, these values can exhibit differences in other writing systems as well. For example, a UA with sufficiently-advanced Thai language processing ability could choose to map different levels of strictness in Thai line-breaking to these keywords, e.g. disallowing breaks within compound words in ''line-break/strict'' mode (e.g. breaking ตัวอย่างการเขียนภาษาไทย as ตัวอย่าง·การเขียน·ภาษาไทย) while allowing more breaks in ''line-break/loose'' (ตัวอย่าง·การ·เขียน·ภาษา·ไทย).
Note: The CSSWG recognizes that in a future edition of the specification finer control over line breaking may be necessary to satisfy high-end publishing requirements.

Hyphenation: the 'hyphens' property

Hyphenation is the controlled splitting of words where they usually would not be allowed to break to improve the layout of paragraphs, typically splitting words at syllabic or morphemic boundaries and often visually indicating the split (usually by inserting a hyphen, U+2010). In some cases, hyphenation may also alter the spelling of a word. Regardless, hyphenation is a rendering effect only: it must have no effect on the underlying document content or on text selection or searching. hyphens/hyphens-character.html hyphens/hyphens-vertical-001.html hyphens/hyphens-vertical-002.html
Hyphenation practices vary across languages, and can involve not just inserting a hyphen before the line break, but inserting a hyphen after the break (or both), inserting a different character than U+2010, or changing the spelling of the word.
Language Unbroken Before After
English Unbroken Un‐ broken
Dutch cafeetje café‐ tje
Hungarian Összeg Ösz‐ szeg
Mandarin tú’àn tú‐ àn
àizēng‐fēnmíng àizēng‐ ‐fēnmíng
Uyghur  [isolated DAL + isolated ALEF + initial MEEM +
					          medial YEH  + final DAL +
					          isolated ALEF MAKSURA] [isolated DAL + isolated ALEF + initial MEEM +
					          final YEH + hyphen ] [ isolated DAL + isolated ALEF MAKSURA]
Cree [ᑲᓯᑕᓂᐘᓂᓂᐠ]
					          (CANADIAN SYLLABICS KA +
					          CANADIAN SYLLABICS SI +
					          CANADIAN SYLLABICS TA +
					          CANADIAN SYLLABICS NI +
					          CANADIAN SYLLABICS WEST-CREE WA +
					          CANADIAN SYLLABICS NI +
					          CANADIAN SYLLABICS NI +
					          CANADIAN SYLLABICS FINAL GRAVE) [ᑲᓯᑕᓂ᐀]
					          (CANADIAN SYLLABICS KA +
					          CANADIAN SYLLABICS SI +
					          CANADIAN SYLLABICS TA +
					          CANADIAN SYLLABICS NI +
					          CANADIAN SYLLABICS HYPHEN) [ᐘᓂᓂᐠ]
					          (CANADIAN SYLLABICS WEST-CREE WA +
					          CANADIAN SYLLABICS NI +
					          CANADIAN SYLLABICS NI +
					          CANADIAN SYLLABICS FINAL GRAVE)
hyphens/i18n/hyphens-i18n-auto-001.html hyphens/i18n/hyphens-i18n-auto-002.html hyphens/i18n/hyphens-i18n-auto-003.html hyphens/i18n/hyphens-i18n-auto-004.html hyphens/i18n/hyphens-i18n-auto-005.html hyphens/i18n/hyphens-i18n-auto-006.html Hyphenation occurs when the line breaks at a valid hyphenation opportunity, which is a type of [=soft wrap opportunity=] that exists within a word where [=hyphenation=] is allowed. In CSS [=hyphenation opportunities=] are controlled with the 'hyphens' property. CSS Text Level 3 does not define the exact rules for [=hyphenation=]; however UAs are strongly encouraged to optimize their choice of break points and to chose language-appropriate hyphenation points. hyphens/hyphens-overflow-001.html Note: The [=soft wrap opportunity=] introduced by the U+002D - HYPHEN-MINUS character or the U+2010 ‐ HYPHEN character is not a [=hyphenation opportunity=], as no visual indication of the split is created when wrapping: these characters are visible whether the line is wrapped at that point or not. Hyphenation opportunities are considered when calculating [=min-content size|min-content intrinsic sizes=]. hyphens/hyphens-auto-min-content.html Note: This allows tables to hyphenate their contents instead of overflowing their containing block, which is particularly important in long-word languages like German.
	Name: hyphens
	Value: none | manual | auto
	Initial: manual
	Applies to: text
	Inherited: yes
	Canonical order: n/a
	Computed value: specified keyword
	Animation type: discrete
	
inheritance.html parsing/hyphens-valid.html parsing/hyphens-invalid.html parsing/hyphens-computed.html hyphens/hyphens-auto-inline-010.html hyphens/hyphens-manual-inline-010.html hyphens/hyphens-manual-inline-011.html hyphens/hyphens-manual-inline-012.html animations/hyphen-no-interpolation.html This property controls whether [=hyphenation=] is allowed to create more [=soft wrap opportunities=] within a line of text. Values have the following meanings:
none
Words are not hyphenated, even if characters inside the word explicitly define [=hyphenation opportunities=]. Note: This does not suppress the existing [=soft wrap opportunities=] introduced by always visible characters such as U+002D - HYPHEN-MINUS or U+2010 ‐ HYPHEN. hyphens/hyphens-none-011.html hyphens/hyphens-none-012.html hyphens/hyphens-none-013.html hyphens/hyphens-none-014.html hyphens/hyphens-none-015.html hyphens/hyphens-none-shy-on-2nd-line-001.html
manual
Words are only hyphenated where there are characters inside the word that explicitly suggest [=hyphenation opportunities=]. The UA must use the appropriate language-specific hyphenation character(s) and should apply any appropriate spelling changes just as for automatic hyphenation at the same point. hyphens/hyphens-overflow-001.html hyphens/hyphens-manual-010.html hyphens/hyphens-manual-011.html hyphens/hyphens-manual-012.html hyphens/hyphens-manual-013.html hyphens/hyphens-out-of-flow-001.html hyphens/hyphens-shaping-001.html hyphens/hyphens-shaping-002.html hyphens/hyphens-span-001.html hyphens/shy-styling-001.html hyphens/i18n/hyphens-i18n-manual-001.html hyphens/i18n/hyphens-i18n-manual-002.html hyphens/i18n/hyphens-i18n-manual-003.html hyphens/i18n/hyphens-i18n-manual-004.html hyphens/i18n/hyphens-i18n-manual-005.html
In Unicode, U+00AD is a conditional "soft hyphen" and U+2010 is an unconditional hyphen. Unicode Standard Annex #14 describes the role of soft hyphens in Unicode line breaking. [[!UAX14]] In HTML, &shy; represents the soft hyphen character, which suggests a hyphenation opportunity. ex&shy;ample
auto
Words may be broken at [=hyphenation opportunities=] determined automatically by a language-appropriate hyphenation resource in addition to those indicated explicitly by a conditional hyphen. Automatic [=hyphenation opportunities=] elsewhere within a word must be ignored if the word contains a conditional hyphen (&shy; or U+00AD SOFT HYPHEN), in favor of the conditional hyphen(s). However, if, even after breaking at such opportunities, a portion of that word is still too long to fit on one line, an automatic hyphenation opportunity may be used. hyphens/hyphens-auto-control.html hyphens/hyphens-auto-001.html hyphens/hyphens-auto-002.html hyphens/hyphens-auto-003.html hyphens/hyphens-auto-004.html hyphens/hyphens-auto-005.html hyphens/hyphens-auto-010.html hyphens/hyphens-out-of-flow-002.html hyphens/hyphens-span-002.html hyphens/hyphens-auto-and-contenteditable-crash.html hyphens/hyphens-auto-last-word-001.html hyphens/hyphens-punctuation-001.html
Correct automatic hyphenation requires a hyphenation resource appropriate to the language of the text being broken. The UA must therefore only automatically hyphenate text for which the content language is known and for which it has an appropriate hyphenation resource. hyphens/hyphens-auto-001.html
Authors should correctly tag their content’s [=content language|language=] (e.g. using the HTML lang attribute or XML xml:lang attribute) in order to obtain correct automatic hyphenation.
The UA may use language-tailored heuristics to exclude certain words from automatic hyphenation. For example, a UA might try to avoid hyphenation in proper nouns by excluding words matching certain capitalization and punctuation patterns. Such heuristics are not defined by this specification. (Note that such heuristics will need to vary by language: English and German, for example, have very different capitalization conventions.) For the purpose of the 'hyphens' property, what constitutes a “word” is UA-dependent. However, inline element boundaries and out-of-flow elements must be ignored when determining word boundaries. hyphens/hyphens-span-001.html hyphens/hyphens-span-002.html hyphens/hyphens-out-of-flow-001.html hyphens/hyphens-out-of-flow-002.html Any glyphs shown due to hyphenation at a [=hyphenation opportunity=] created by a conditional hyphen character (such as U+00AD SOFT HYPHEN) are represented by that character and are styled according to the properties applied to it. hyphens/shy-styling-001.html When shaping scripts such as Arabic are allowed to break within words due to hyphenation, the characters must still be shaped as if the word were [[#word-break-shaping|not broken]] (see [[#word-break-shaping]]). hyphens/hyphens-shaping-001.html hyphens/hyphens-shaping-002.html
For example, if the Uyghur word “داميدى” were hyphenated, it would appear as [isolated DAL + isolated ALEF + initial MEEM +
		          medial YEH + hyphen + line-break + final DAL +
		          isolated ALEF MAKSURA] not as [isolated DAL + isolated ALEF + initial MEEM +
		          final YEH + hyphen + line-break + isolated DAL +
		          isolated ALEF MAKSURA] .

Overflow Wrapping: the 'overflow-wrap'/'word-wrap' property

	Name: overflow-wrap, word-wrap
	Value: normal | break-word | anywhere
	Initial: normal
	Applies to: text
	Inherited: yes
	Canonical order: n/a
	Computed value: specified keyword
	Animation type: discrete
	
inheritance.html parsing/overflow-wrap-invalid.html parsing/overflow-wrap-valid.html parsing/overflow-wrap-computed.html parsing/word-wrap-invalid.html parsing/word-wrap-valid.html parsing/word-wrap-computed.html overflow-wrap/overflow-wrap-anywhere-span-001.html overflow-wrap/overflow-wrap-anywhere-span-002.html overflow-wrap/overflow-wrap-break-word-span-001.html overflow-wrap/overflow-wrap-break-word-span-002.html overflow-wrap/overflow-wrap-break-word-long-crash.html overflow-wrap/overflow-wrap-break-word-white-space-crash.html overflow-wrap/overflow-wrap-break-word-white-space-crash-002.html overflow-wrap/overflow-wrap-anywhere-inline-002.tentative.html This property specifies whether the UA may break at otherwise disallowed points within a line to prevent overflow, when an otherwise-unbreakable string is too long to fit within the line box. It only has an effect when 'white-space' allows [=wrapping=]. Possible values: overflow-wrap/overflow-wrap-002.html
normal
Lines may break only at allowed break points. However, the restrictions introduced by ''word-break: keep-all'' may be relaxed to match ''word-break: normal'' if there are no otherwise-acceptable break points in the line. overflow-wrap/overflow-wrap-004.html overflow-wrap/overflow-wrap-normal-keep-all-001.html
anywhere
An otherwise unbreakable sequence of [=characters=] may be broken at an arbitrary point if there are no otherwise-acceptable break points in the line. Shaping characters are still shaped as if the word were not broken, and grapheme clusters must stay together as one unit. No hyphenation character is inserted at the break point. [=Soft wrap opportunities=] introduced by ''overflow-wrap/anywhere'' are considered when calculating [=min-content size|min-content intrinsic sizes=]. overflow-wrap/overflow-wrap-min-content-size-001.html overflow-wrap/overflow-wrap-min-content-size-002.html overflow-wrap/overflow-wrap-min-content-size-003.html overflow-wrap/overflow-wrap-anywhere-001.html overflow-wrap/overflow-wrap-anywhere-003.html overflow-wrap/overflow-wrap-anywhere-006.html overflow-wrap/overflow-wrap-anywhere-007.html overflow-wrap/overflow-wrap-anywhere-008.html overflow-wrap/overflow-wrap-anywhere-009.html overflow-wrap/overflow-wrap-anywhere-010.html overflow-wrap/overflow-wrap-anywhere-011.html overflow-wrap/overflow-wrap-anywhere-inline-001.html overflow-wrap/overflow-wrap-anywhere-inline-002.tentative.html overflow-wrap/overflow-wrap-anywhere-inline-003.tentative.html overflow-wrap/overflow-wrap-anywhere-inline-004.tentative.html overflow-wrap/overflow-wrap-anywhere-fit-content-001.html overflow-wrap/overflow-wrap-min-content-size-005.html overflow-wrap/overflow-wrap-min-content-size-007.html overflow-wrap/overflow-wrap-cluster-002.html overflow-wrap/overflow-wrap-shaping-002.html white-space/break-spaces-before-first-char-009.html white-space/break-spaces-before-first-char-013.html white-space/break-spaces-before-first-ideographic-char-009.html white-space/break-spaces-before-first-ideographic-char-013.html word-break/word-break-min-content-001.html word-break/word-break-min-content-002.html word-break/word-break-min-content-003.html word-break/word-break-min-content-004.html word-break/word-break-min-content-005.html word-break/word-break-min-content-006.html white-space/pre-wrap-009.html white-space/pre-wrap-010.html white-space/break-spaces-with-overflow-wrap-002.html white-space/break-spaces-with-overflow-wrap-004.html white-space/break-spaces-with-overflow-wrap-006.html white-space/break-spaces-with-overflow-wrap-008.html white-space/break-spaces-with-overflow-wrap-010.html overflow-wrap/overflow-wrap-min-content-size-009.html
break-word
As for ''overflow-wrap/anywhere'' except that soft wrap opportunities introduced by ''overflow-wrap/break-word'' are not considered when calculating [=min-content size|min-content intrinsic sizes=]. overflow-wrap/overflow-wrap-001.html overflow-wrap/overflow-wrap-break-word-001.html overflow-wrap/overflow-wrap-break-word-003.html overflow-wrap/overflow-wrap-break-word-008.html overflow-wrap/overflow-wrap-break-word-009.html overflow-wrap/overflow-wrap-break-word-010.html overflow-wrap/overflow-wrap-min-content-size-004.html overflow-wrap/overflow-wrap-min-content-size-006.html overflow-wrap/overflow-wrap-min-content-size-008.html overflow-wrap/overflow-wrap-break-word-fit-content-001.html overflow-wrap/overflow-wrap-cluster-001.html overflow-wrap/overflow-wrap-shaping-001.html white-space/break-spaces-before-first-char-008.html white-space/break-spaces-before-first-char-012.html white-space/break-spaces-before-first-ideographic-char-008.html white-space/break-spaces-before-first-ideographic-char-012.html overflow-wrap/overflow-wrap-break-word-keep-all-001.html white-space/break-spaces-with-overflow-wrap-001.html white-space/break-spaces-with-overflow-wrap-003.html white-space/break-spaces-with-overflow-wrap-005.html white-space/break-spaces-with-overflow-wrap-007.html white-space/break-spaces-with-overflow-wrap-009.html white-space/trailing-ideographic-space-013.html white-space/trailing-ideographic-space-014.html white-space/trailing-ideographic-space-015.html white-space/trailing-ideographic-space-016.html
For legacy reasons, UAs must treat 'word-wrap' as a [=legacy name alias=] of the 'overflow-wrap' property. overflow-wrap/word-wrap-alias.html overflow-wrap/word-wrap-001.html overflow-wrap/word-wrap-002.html overflow-wrap/word-wrap-004.html

Shaping Across Intra-word Breaks

When shaping scripts such as Arabic [=wrap=] at unforced [=soft wrap opportunities=] within words (such as when breaking due to ''word-break: break-all'', ''line-break: anywhere'', ''overflow-wrap: break-word'', ''overflow-wrap: anywhere'', or when [=hyphenating=]) the characters must still be shaped (their joining forms chosen) as if the word were still whole. hyphens/hyphens-shaping-001.html hyphens/hyphens-shaping-002.html line-break/line-break-shaping-001.html overflow-wrap/overflow-wrap-shaping-001.html overflow-wrap/overflow-wrap-shaping-002.html word-break/word-break-break-all-004.html
For example, if the word “نوشتن” is broken between the “ش” and “ت”, the “ش” still takes its initial form (“ﺷ”), and the “ت” its medial form (“ﺘ”)-- forming as in “ﻧﻮﺷ | ﺘﻦ”, not as in “نوش | تن”.

Alignment and Justification

Alignment and justification controls how inline content is distributed within a line box.

Text Alignment: the 'text-align' shorthand

	Name: text-align
	Value: start | end | left | right | center | justify | match-parent | justify-all
	Initial: start
	Applies to: block containers
	Inherited: yes
	Canonical order: n/a
	Animation type: discrete
	
inheritance.html parsing/text-align-valid.html parsing/text-align-invalid.html parsing/text-align-computed.html text-align/text-align-webkit-match-parent.html c546-txt-align-000.xht text-align-005.xht text-align-applies-to-001.xht text-align-applies-to-002.xht text-align-applies-to-003.xht text-align-applies-to-005.xht text-align-applies-to-006.xht text-align-applies-to-007.xht text-align-applies-to-008.xht text-align-applies-to-009.xht text-align-applies-to-010.xht text-align-applies-to-011.xht text-align-applies-to-012.xht text-align-applies-to-013.xht text-align-applies-to-014.xht text-align-applies-to-015.xht text-align-inherit-001.xht text-align-bidi-011.xht This [=shorthand property=] sets the 'text-align-all' and 'text-align-last' properties and describes how the inline-level content of a block is aligned along the inline axis if the content does not completely fill the line box. Values other than ''justify-all'' or ''match-parent'' are assigned to 'text-align-all' and reset 'text-align-last' to ''text-align-last/auto''. Values have the following meanings:
start
Inline-level content is aligned to the start edge of the line box. text-align/text-align-006.html text-align/text-align-start-001.html text-align/text-align-start-002.html text-align/text-align-start-003.html text-align/text-align-start-004.html text-align/text-align-start-005.html text-align/text-align-start-006.html text-align/text-align-start-007.html text-align/text-align-start-008.html text-align/text-align-start-009.html text-align/text-align-start-010.html text-align/text-align-start-014.html text-align/text-align-start-015.html text-align/text-align-start-016.html text-align/text-align-start-017.html text-align/text-align-start-018.html text-align/text-align-start-019.html text-align/text-align-start-020.html text-align/text-align-start-021.html
end
Inline-level content is aligned to the end edge of the line box. text-align/text-align-007.html text-align/text-align-end-001.html text-align/text-align-end-002.html text-align/text-align-end-003.html text-align/text-align-end-004.html text-align/text-align-end-005.html text-align/text-align-end-006.html text-align/text-align-end-007.html text-align/text-align-end-008.html text-align/text-align-end-009.html text-align/text-align-end-010.html text-align/text-align-end-014.html text-align/text-align-end-015.html text-align/text-align-end-016.html text-align/text-align-end-017.html text-align/text-align-end-018.html text-align/text-align-end-019.html text-align/text-align-end-020.html text-align/text-align-end-021.html
left
Inline-level content is aligned to the [=line-left=] edge of the line box. (In vertical writing modes, this can be either the physical top or bottom, depending on 'writing-mode'.) [[CSS-WRITING-MODES-4]] text-align-001.xht text-align-bidi-001.xht text-align-bidi-006.xht text-align-bidi-007.xht
right
Inline-level content is aligned to the [=line-right=] edge of the line box. (In vertical writing modes, this can be either the physical top or bottom, depending on 'writing-mode'.) [[CSS-WRITING-MODES-4]] text-align-002.xht text-align-bidi-005.xht
center
Inline-level content is centered within the line box. text-align-003.xht text-align-bidi-002.xht text-align-bidi-003.xht text-align-bidi-004.xht text-align-inherit-001.xht text-align/text-align-center-last-center.html
justify
Text is justified according to the method specified by the 'text-justify' property, in order to exactly fill the line box. Unless otherwise specified by 'text-align-last', the last line before a forced break or the end of the block is ''text-align/start''-aligned. text-align/text-align-justify-001.html text-align/text-align-justify-002.html text-align/text-align-justify-003.html text-align/text-align-justify-004.html text-align/text-align-justify-005.html text-align/text-align-justify-006.html text-align/text-align-justify-shy-001.html letter-spacing-justify-001.xht text-align-004.xht text-align-bidi-008.xht text-align-bidi-009.xht text-align-bidi-010.xht text-align-bidi-012.xht text-align-bidi-013.xht text-align-white-space-002.xht text-align-white-space-004.xht text-align-white-space-006.xht text-align-white-space-008.xht word-spacing-justify-001.xht
justify-all
Sets both 'text-align-all' and 'text-align-last' to ''text-align/justify'', forcing the last line to justify as well. text-align/text-align-justifyall-001.html text-align/text-align-justifyall-002.html text-align/text-align-justifyall-003.html text-align/text-align-justifyall-004.html text-align/text-align-justifyall-005.html text-align/text-align-justifyall-006.html letter-spacing/letter-spacing-bidi-003.xht
match-parent
This value behaves the same as ''inherit'' (computes to its parent’s computed value) except that an [=inherited value=] of ''text-align/start'' or ''text-align/end'' is interpreted against the parent’s 'direction' value and results in a computed value of either ''text-align/left'' or ''text-align/right''. Computes to ''text-align/start'' when specified on the [=root element=]. text-align/text-align-match-parent-001.html text-align/text-align-match-parent-002.html text-align/text-align-match-parent-01.html text-align/text-align-match-parent-02.html text-align/text-align-match-parent-03.html text-align/text-align-match-parent-04.html text-align/text-align-match-parent-root-ltr.html text-align/text-align-match-parent-root-rtl.html text-align/text-align-match-parent-root-logical.html When specified on the 'text-align' shorthand, sets both 'text-align-all' and 'text-align-last' to ''text-align/match-parent''. text-align/text-align-match-parent-05.html
A block of text is a stack of [=line boxes=]. This property specifies how the inline-level boxes within each line box align with respect to the start and end sides of the line box. Alignment is not with respect to the [[CSS2/visuren#viewport|viewport]] or containing block. In the case of ''justify'', the UA may stretch or shrink any inline boxes by [[#text-justify-property|adjusting]] their text. (See 'text-justify'.) If an element’s [=white space=] is not [=collapsible=], then the UA is not required to adjust its text for the purpose of justification and may instead treat the text as having no [=justification opportunities=]. If the UA chooses to adjust the text, then it must ensure that tab stops continue to line up as required by the [[#white-space-rules|white space processing rules]]. text-align-white-space-001.xht text-align-white-space-005.xht text-align/text-align-justify-tabs-001.html text-align/text-align-justify-tabs-002.html text-align/text-align-justify-tabs-003.html text-align/text-align-justify-tabs-004.html If (after justification, if any) the inline contents of a line box are too long to fit within it, then the contents are start-aligned: any content that doesn’t fit overflows the line box’s end edge. See [[#bidi-linebox]] for details on how to determine the start and end edges of a line box.

Default Text Alignment: the 'text-align-all' property

	Name: text-align-all
	Value: start | end | left | right | center | justify | match-parent
	Initial: start
	Applies to: block containers
	Inherited: yes
	Computed value: keyword as specified, except for ''match-parent'' which computes as defined above
	Canonical order: n/a
	Animation type: discrete
	
inheritance.html parsing/text-align-all-valid.html parsing/text-align-all-invalid.html This longhand of the 'text-align' [=shorthand property=] specifies the inline alignment of all lines of inline content in the block container, except for last lines overridden by a non-''text-align-last/auto'' value of 'text-align-last'. See 'text-align' for a full description of values.

Authors should use the 'text-align' shorthand instead of this property.

Last Line Alignment: the 'text-align-last' property

	Name: text-align-last
	Value: auto | start | end | left | right | center | justify | match-parent
	Initial: auto
	Applies to: block containers
	Inherited: yes
	Canonical order: n/a
	Computed value: specified keyword
	Animation type: discrete
	
inheritance.html parsing/text-align-last-valid.html parsing/text-align-last-invalid.html parsing/text-align-last-computed.html text-align/text-align-last-013.html text-align/text-align-last-014.html This property describes how the last line of a block or a line right before a [=forced line break=] is aligned. text-align/text-align-last-001.html text-align/text-align-last-002.html text-align/text-align-last-003.html text-align/text-align-last-004.html text-align/text-align-last-005.html text-align/text-align-last-006.html text-align/text-align-last-010.html text-align/text-align-last-011.html text-align/text-align-last-012.html text-align/text-align-last-wins-001.html If auto is specified, content on the affected line is aligned per 'text-align-all' unless 'text-align-all' is set to ''justify'', in which case it is ''text-align/start''-aligned. All other values are interpreted as described for 'text-align'. text-align/text-align-last-007.html text-align/text-align-last-008.html text-align/text-align-last-009.html text-align/text-align-center-last-center.html text-align/text-align-center-last-default.html text-align/text-align-center-last-end.html text-align/text-align-center-last-justify.html text-align/text-align-center-last-start.html text-align/text-align-default-last-default.html text-align/text-align-end-last-center.html text-align/text-align-end-last-default.html text-align/text-align-end-last-end.html text-align/text-align-end-last-justify.html text-align/text-align-end-last-start.html text-align/text-align-inline-end-crash.html text-align/text-align-justify-last-center.html text-align/text-align-justify-last-default.html text-align/text-align-justify-last-end.html text-align/text-align-justify-last-justify.html text-align/text-align-justify-last-start.html text-align/text-align-last-center.html text-align/text-align-last-end.html text-align/text-align-last-interpolation.html text-align/text-align-last-justify-rtl.html text-align/text-align-last-justify.html text-align/text-align-last-simple.html text-align/text-align-last-start.html text-align/text-align-start-last-center.html text-align/text-align-start-last-default.html text-align/text-align-start-last-end.html text-align/text-align-start-last-justify.html text-align/text-align-start-last-start.html text-align/text-align-match-parent-05.html text-align/text-align-last-015.html

Justification Method: the 'text-justify' property

	Name: text-justify
	Value: auto | none | inter-word | inter-character
	Initial: auto
	Applies to: text
	Inherited: yes
	Canonical order: n/a
	Computed value: specified keyword (except for the ''distribute'' legacy value)
	Animation type: discrete
	
inheritance.html parsing/text-justify-valid.html parsing/text-justify-invalid.html parsing/text-justify-computed.html text-justify/text-justify-006.html text-justify/text-justify-interpolation.html This property selects the justification method used when a line’s alignment is set to ''justify'' (see 'text-align'). The property applies to text, but is inherited from block containers to the root inline box containing their inline-level contents. It takes the following values: text-justify/text-justify-006.html
auto
The UA determines the justification algorithm to follow, based on a balance between performance and adequate presentation quality. Since justification rules vary by [=writing system=] and [=content language|language=], UAs should, where possible, use a justification algorithm appropriate to the text. text/letter-spacing-justify-001.xht text/word-spacing-justify-001.xht
For example, the UA could use by default a justification method that is a simple universal compromise for all writing systems-- such as primarily expanding [=word separators=] and between CJK [=typographic letter units=] along with secondarily expanding between Southeast Asian [=typographic letter units=]. Then, in cases where the [=content language=] of the paragraph is known, it could choose a more language-tailored justification behavior e.g. following the Requirements for Japanese Text Layout for Japanese [[JLREQ]], using cursive elongation for Arabic, using ''inter-word'' for German, etc.
Two lines of calligraphic Arabic end together
				          due to a mix of compressed and swash forms.
An example of cursively-justified Arabic text, rendered by Tasmeem. Like English, Arabic can be justified by adjusting the spacing between words, but in most styles it can also be justified by calligraphically elongating or compressing the letterforms themselves. In this example, the upper text is extended to fill the line by the use of elongated (kashida) forms and swash forms, while the bottom line is compressed slightly by using a stacked combination for the characters between ت and م. By employing traditional calligraphic techniques, a typesetter can justify the line while preserving flow and color, providing a very high quality justification effect. However, this is by its nature a very script-specific effect.
Extra space is partly to spaces and partly among CJK and Thai letters.
Mixed-script text with ''text-justify: auto'': this interpretation uses a universal-compromise justification method, expanding at spaces as well as between CJK and Southeast Asian letters. This effectively uses inter-word + inter-ideograph spacing for lines that have word-separators and/or CJK characters and falls back to inter-cluster behavior for lines that don’t or for which the space stretches too far.
none
Justification is disabled: there are no [=justification opportunities=] within the text. text-justify/text-justify-001.html text-justify/text-justify-006.html text-justify-none-001.html
No extra space is inserted.
Mixed-script text with ''text-justify: none''
Note: This value is intended for use in user stylesheets to improve readability or for accessibility purposes.
inter-word
Justification adjusts spacing at [=word separators=] only (effectively varying the used 'word-spacing' on the line). This behavior is typical for languages that separate words using spaces, like English or Korean. text-justify-inter-word-001.html text-justify-word-separators.html
Extra space is equally distributed mainly to spaces.
Mixed-script text with ''text-justify: inter-word''
inter-character
Justification adjusts spacing between each pair of adjacent [=typographic character units=] (effectively varying the used 'letter-spacing' on the line). This value is sometimes used in East Asian systems such as Japanese. text-justify/text-justify-002.html text-justify-inter-character-001.html
Extra space is equally distributed
				          at points between spaces and letters of all writing systems.
Mixed-script text with ''text-justify: inter-character''
For legacy reasons, UAs must also support the alternate keyword distribute which must compute to ''inter-character'', thus having the exact same meaning and behavior. UAs may treat this as a [=legacy value alias=]. text-justify/text-justify-003.html parsing/text-justify-computed-legacy.html text-justify/text-justify-distribute-001.html

Since optimal justification is [=content language|language=]-sensitive, authors should correctly language-tag their content for the best results. Note: The guidelines in this level of CSS do not describe a complete justification algorithm. They are merely a minimum set of requirements that a complete algorithm should meet. Limiting the set of requirements gives UAs some latitude in choosing a justification algorithm that meets their needs and desired balance of quality, speed, and complexity.

Expanding and Compressing Text

When justifying text, the user agent takes the remaining space between the ends of a line’s contents and the edges of its line box, and distributes that space throughout its content so that the contents exactly fill the line box. The user agent may alternatively distribute negative space, putting more content on the line than would otherwise fit under normal spacing conditions. A justification opportunity is a point where the justification algorithm may alter spacing within the text. A justification opportunity can be provided by a single [=typographic character unit=] (such as a [=word separator=]), or by the juxtaposition of two [=typographic character units=]. As with controls for [[#line-break-details|soft wrap opportunities]], whether a [=typographic character unit=] provides a [=justification opportunity=] is controlled by the 'text-justify' value of its parent; similarly, whether a [=justification opportunity=] exists between two consecutive [=typographic character units=] is determined by the 'text-justify' value of their nearest common ancestor. Space distributed by justification is in addition to the spacing defined by the 'letter-spacing' or 'word-spacing' properties. When such additional space is distributed to a [=word separator=] [=justification opportunity=], it is applied under the same rules as for 'word-spacing'. Similarly, when space is distributed to a [=justification opportunity=] between two [=typographic character units=], should be applied under the same rules as for 'letter-spacing'. A justification algorithm may divide [=justification opportunities=] into different priority levels. All [=justification opportunities=] within a given level are expanded or compressed at the same priority, regardless of which [=typographic character units=] created that opportunity. For example, if [=justification opportunities=] between two Han characters and between two Latin letters are defined to be at the same level (as they are in the ''inter-character'' justification style), they are not treated differently because they originate from different [=typographic character units=]. It is not defined in this level whether or how other factors (such as font size, letter-spacing, glyph shape, position within the line, etc.) may influence the distribution of space to [=justification opportunities=] within the line. The UA may enable or break optional ligatures or use other font features such as alternate glyphs or glyph compression to help justify the text under any method. This behavior is not controlled by this level of CSS. However, UAs must not break required ligatures or otherwise disable features required to correctly shape complex scripts. If a [=justification opportunity=] exists within a line, and [[#text-align-property|text alignment]] specifies full justification (''text-align/justify'') for that line, it must be justified.

Handling Symbols and Punctuation

When determining [=justification opportunities=], a [=typographic character unit=] from the Unicode Symbols (S*) and Punctuation (P*) classes is generally treated the same as a [=typographic letter unit=] of the same script (or, if the character’s script property is Common, then as a [=typographic letter unit=] of the dominant script). However, by typographic tradition there may be additional rules controlling the justification of symbols and punctuation. Therefore, the UA may reassign specific characters or introduce additional levels of prioritization to handle [=justification opportunities=] involving symbols and punctuation.
For example, there are traditionally no [=justification opportunities=] between consecutive U+2014 — EM DASH, U+2015 ― HORIZONTAL BAR, U+2026 … HORIZONTAL ELLIPSIS, or U+2025 ‥ TWO DOT LEADER characters [[JLREQ]]; thus a UA might assign these characters to a “never” prioritization level. As another example, certain full-width punctuation characters (such as U+301A 〚 LEFT WHITE SQUARE BRACKET) are considered to contain a [=justification opportunity=] in Japanese. The UA might therefore assign these characters to a higher prioritization level than the opportunities between ideographic characters.

Unexpandable Text

If the inline contents of a line cannot be stretched to the full width of the line box, then they must be aligned as specified by the 'text-align-last' property. (If 'text-align-last' is ''justify'', then they must be aligned as for ''text-align/center''.) text-align/text-align-last-empty-inline.html

Cursive Scripts

Justification must not introduce gaps between the joined [=typographic letter units=] of [=cursive scripts=] such as Arabic. If it is able, the UA may translate space distributed to [=justification opportunities=] within a run of such [=typographic letter units=] into some form of cursive elongation for that run. It otherwise must assume that no [=justification opportunity=] exists between any pair of [=typographic letter units=] in [=cursive script=] (regardless of whether they join). text-justify/text-justify-004.html text-justify/text-justify-005.html
The following are examples of unacceptable justification:
Adding gaps between every pair of Arabic letters
Adding gaps between every pair of unjoined Arabic letters
Some font designs allow for the use of the tatweel character for justification. A UA that performs tatweel-based justification must properly handle the rules for its use. Note that correct insertion of tatweel characters depends on context, including the letter-combinations involved, location within the word, and location of the word within the line.

Minimum Requirements for ''text-justify/auto'' Justification

For ''text-justify/auto'' justification, this specification does not define what all of the [=justification opportunities=] are, how they are prioritized, or when and how multiple levels of [=justification opportunities=] interact. However, it does require that: Further information on text justification can be found in (or submitted to) “Approaches to Full Justification”, which indexes by writing system and language, and is maintained by the W3C Internationalization Working Group. [[JUSTIFY]]

Spacing

CSS offers control over text spacing via the 'word-spacing' and 'letter-spacing' properties, which specify additional space around [=word separators=] or between [=typographic character units=], respectively.

Word Spacing: the 'word-spacing' property

	Name: word-spacing
	Value: normal | <>
	Initial: normal
	Applies to: text
	Inherited: yes
	Percentages: N/A
	Computed value: an absolute length
	Animation type: by computed value type
	Canonical order: n/a
	
inheritance.html parsing/word-spacing-valid.html parsing/word-spacing-invalid.html parsing/word-spacing-computed.html animations/word-spacing-interpolation.html animations/word-spacing-composition.html c541-word-sp-000.xht c541-word-sp-001.xht word-spacing-101.xht word-spacing-applies-to-001.xht word-spacing-applies-to-002.xht word-spacing-applies-to-003.xht word-spacing-applies-to-005.xht word-spacing-applies-to-006.xht word-spacing-applies-to-007.xht word-spacing-applies-to-008.xht word-spacing-applies-to-009.xht word-spacing-applies-to-010.xht word-spacing-applies-to-011.xht word-spacing-applies-to-012.xht word-spacing-applies-to-013.xht word-spacing-applies-to-014.xht word-spacing-applies-to-015.xht word-spacing-justify-001.xht This property specifies additional spacing between “words”. Values are interpreted as defined below:
normal
No additional spacing is applied. Computes to zero. word-spacing-100.xht word-spacing/word-spacing-computed-001.html
<length>
Specifies extra spacing in addition to the intrinsic inter-word spacing defined by the font. tab-size/tab-size-spacing-001.html word-spacing-004.xht word-spacing-005.xht word-spacing-006.xht word-spacing-007.xht word-spacing-008.xht word-spacing-016.xht word-spacing-017.xht word-spacing-018.xht word-spacing-019.xht word-spacing-020.xht word-spacing-028.xht word-spacing-029.xht word-spacing-030.xht word-spacing-031.xht word-spacing-032.xht word-spacing-040.xht word-spacing-041.xht word-spacing-042.xht word-spacing-043.xht word-spacing-044.xht word-spacing-052.xht word-spacing-053.xht word-spacing-054.xht word-spacing-055.xht word-spacing-056.xht word-spacing-064.xht word-spacing-065.xht word-spacing-066.xht word-spacing-067.xht word-spacing-068.xht word-spacing-076.xht word-spacing-077.xht word-spacing-078.xht word-spacing-079.xht word-spacing-080.xht word-spacing-088.xht word-spacing-089.xht word-spacing-090.xht word-spacing-091.xht word-spacing-092.xht word-spacing-097.xht word-spacing-098.xht word-spacing-099.xht
Additional spacing is applied to each [=word separator=] left in the text after the [[#white-space-rules|white space processing rules]] have been applied, and should be applied half on each side of the character unless otherwise dictated by typographic tradition. Values may be negative, but there may be implementation-dependent limits. word-spacing-remove-space-001.xht word-spacing-remove-space-002.xht word-spacing-remove-space-003.xht word-spacing-remove-space-004.xht word-spacing-remove-space-005.xht word-spacing-remove-space-006.xht word-spacing/word-spacing-negative-value-001.html Word-separator characters are [=typographic character units=] whose primary purpose and general usage is to separate words. In Unicode this includes (but is not exhaustively defined as) the space (U+0020), the no-break space (U+00A0), the Ethiopic word space (U+1361), the Aegean word separators (U+10100,U+10101), the Ugaritic word divider (U+1039F), and the Phoenician word separator (U+1091F). [[UNICODE]] word-spacing-characters-001.xht Note: Neither punctuation in general, nor fixed-width spaces (such as U+3000 and U+2000 through U+200A), are considered [=word-separator characters=], because even though they frequently happen to separate words, their primary purpose is not to separate words. word-spacing-characters-002.xht If there are no [=word-separator characters=], or if a word-separating character has a zero advance width (such as U+200B ZERO WIDTH SPACE) then the user agent must not create an additional spacing between words. word-spacing-characters-003.xht

Tracking: the 'letter-spacing' property

	Name: letter-spacing
	Value: normal | <>
	Initial: normal
	Applies to: inline boxes and text
	Inherited: yes
	Computed value: an absolute length
	Animation type: by computed value type
	Canonical order: n/a
	
inheritance.html parsing/letter-spacing-valid.html parsing/letter-spacing-invalid.html parsing/letter-spacing-computed.html animations/letter-spacing-interpolation.html animations/letter-spacing-composition.html letter-spacing/letter-spacing-nesting-003.xht letter-spacing/letter-spacing-bidi-003.xht letter-spacing/letter-spacing-bidi-004.xht letter-spacing/letter-spacing-bidi-005.xht letter-spacing/letter-spacing-200.html letter-spacing/letter-spacing-201.html letter-spacing/letter-spacing-203.html letter-spacing/letter-spacing-206.html c542-letter-sp-000.xht c542-letter-sp-001.xht letter-spacing-applies-to-001.xht letter-spacing-applies-to-002.xht letter-spacing-applies-to-003.xht letter-spacing-applies-to-005.xht letter-spacing-applies-to-006.xht letter-spacing-applies-to-007.xht letter-spacing-applies-to-008.xht letter-spacing-applies-to-009.xht letter-spacing-applies-to-010.xht letter-spacing-applies-to-011.xht letter-spacing-applies-to-012.xht letter-spacing-applies-to-013.xht letter-spacing-applies-to-014.xht letter-spacing-applies-to-015.xht This property specifies additional spacing (commonly called tracking) between adjacent [=typographic character units=]. Letter-spacing is applied after [[css-writing-modes-4#text-direction|bidi reordering]] and is in addition to [[css-fonts-3#font-kerning-prop|kerning]] and 'word-spacing'. [[CSS-WRITING-MODES-4]] [[CSS-FONTS-3]] Depending on the justification rules in effect, user agents may further increase or decrease the space between [=typographic character units=] in order to [[#text-justify-property|justify text]]. letter-spacing/letter-spacing-bidi-001.html letter-spacing/letter-spacing-bidi-004.xht letter-spacing/letter-spacing-nesting-003.xht letter-spacing/letter-spacing-bidi-003.xht letter-spacing/letter-spacing-bidi-004.xht letter-spacing/letter-spacing-bidi-005.xht letter-spacing/letter-spacing-206.html letter-spacing/letter-spacing-211.html letter-spacing/letter-spacing-212.html letter-spacing/letter-spacing-bengali-yaphala-001.html bidi-005.xht bidi-006.xht bidi-007.xht bidi-008.xht bidi-009.xht bidi-010.xht bidi-text/bidi-005a.xht bidi-text/bidi-005b.xht bidi-text/bidi-006a.xht bidi-text/bidi-006b.xht bidi-text/bidi-007b.xht bidi-text/bidi-008b.xht bidi-text/bidi-009b.xht bidi-text/bidi-010b.xht text/letter-spacing-justify-001.xht Values have the following meanings:
normal
No additional spacing is applied. Computes to zero. letter-spacing-100.xht
<length>
Specifies additional spacing between [=typographic character units=]. Values may be negative, but there may be implementation-dependent limits. tab-size/tab-size-spacing-001.html letter-spacing-004.xht letter-spacing-005.xht letter-spacing-006.xht letter-spacing-007.xht letter-spacing-008.xht letter-spacing-016.xht letter-spacing-017.xht letter-spacing-018.xht letter-spacing-019.xht letter-spacing-020.xht letter-spacing-028.xht letter-spacing-029.xht letter-spacing-030.xht letter-spacing-031.xht letter-spacing-032.xht letter-spacing-040.xht letter-spacing-041.xht letter-spacing-042.xht letter-spacing-043.xht letter-spacing-044.xht letter-spacing-052.xht letter-spacing-053.xht letter-spacing-054.xht letter-spacing-055.xht letter-spacing-056.xht letter-spacing-064.xht letter-spacing-065.xht letter-spacing-066.xht letter-spacing-067.xht letter-spacing-068.xht letter-spacing-076.xht letter-spacing-077.xht letter-spacing-078.xht letter-spacing-079.xht letter-spacing-080.xht letter-spacing-088.xht letter-spacing-089.xht letter-spacing-090.xht letter-spacing-091.xht letter-spacing-092.xht letter-spacing-097.xht letter-spacing-098.xht letter-spacing-099.xht letter-spacing-101.xht letter-spacing-102.xht
For legacy reasons, a computed 'letter-spacing' of zero yields a [=resolved value=] ({{getComputedStyle()}} return value) of ''letter-spacing/normal''. For the purpose of 'letter-spacing', each consecutive run of [=atomic inlines=] (such as images and inline blocks) is treated as a single [=typographic character unit=]. letter-spacing/letter-spacing-204.html Letter-spacing must not be applied at the beginning of a line. Whether letter-spacing is applied at the end of a line is undefined in this level. letter-spacing/letter-spacing-end-of-line-001.html tab-size/tab-size-spacing-001.html letter-spacing/letter-spacing-200.html letter-spacing/letter-spacing-201.html white-space/white-space-letter-spacing-001.html
When letter-spacing is not applied at the beginning or end of a line, text always fits flush with the edge of the block.
			p { letter-spacing: 1em; }
		
<p>abc</p>

a b c

a b c

UAs therefore really should not [[RFC6919]] append letter spacing to the right or trailing edge of a line:

a b c 

Letter spacing between two [=typographic character units=] effectively “belongs” to the innermost element that contains the two [=typographic character units=]: the total letter spacing between two adjacent [=typographic character units=] (after bidi reordering) is specified by and rendered within the innermost element that contains the boundary between the two [=typographic character units=]. However, the UA may instead attach letter-spacing at element boundaries to one or the other [=typographic character unit=] using the letter-spacing value pertaining to its containing element. Note: This secondary behavior is permitted in this level due to Web-compat concerns. letter-spacing/letter-spacing-bidi-002.html letter-spacing/letter-spacing-bidi-004.xht letter-spacing/letter-spacing-bidi-005.xht letter-spacing/letter-spacing-nesting-001.html letter-spacing/letter-spacing-nesting-002.html letter-spacing/letter-spacing-nesting-003.xht letter-spacing/letter-spacing-203.html letter-spacing/letter-spacing-205.html
An inline box is expected to only include letter spacing between characters completely contained within that element, thus excluding letter spacing on the right or trailing edge of the element:
p { letter-spacing: 1em; }
<p>a<span>bb</span>c</p>

a b b c

a b b c

Consequently a given value of 'letter-spacing' is expected to only affect the spacing between characters completely contained within the element for which it is specified:
			p    { letter-spacing: 1em; }
			span { letter-spacing: 2em; }
		
<p>a<span>bb</span>c</p>

a b  b c

This further implies that applying 'letter-spacing' to an element containing only a single character has no effect on the rendered result:

			p    { letter-spacing: 1em; }
			span { letter-spacing: 2em; }
		
<p>a<span>b</span>c</p>

a b c

Since letter spacing is inserted after RTL reordering, the letter spacing applied to the inner span below likewise has no effect, since after reordering the "c" doesn’t end up next to "א":
			p    { letter-spacing: 1em; }
			span { letter-spacing: 2em; }
		

			<!-- abc followed by Hebrew letters alef (א), bet (ב) and gimel (ג) -->
			<!-- Reordering will display these in reverse order. -->
			<p>ab<span>cא</span>בג</p>
		

a b c א ב ג

Letter spacing ignores invisible zero-width formatting characters (such as those from the Unicode Cf category). Spacing must be added as if those characters did not exist in the document. letter-spacing/letter-spacing-control-chars-001.html letter-spacing/letter-spacing-202.html
For example, 'letter-spacing' applied to A&#x200B;B is identical to AB, regardless of where any element boundaries might fall.
When the effective spacing between two characters is not zero (due to either [[#text-justify-property|justification]] or a non-zero value of 'letter-spacing'), user agents should not apply optional ligatures, i.e. those that are not defined as required for fundamentally correct glyph shaping. However, ligatures and other font features specified via the low-level 'font-feature-settings' property take precedence over this rule. See [[css-fonts-3#feature-precedence]]. letter-spacing/letter-spacing-ligatures-001.html letter-spacing/letter-spacing-ligatures-002.html letter-spacing/letter-spacing-ligatures-003.html letter-spacing/letter-spacing-ligatures-004.html
For example, if the word “filial” is letter-spaced, an “fi” ligature should not be used as it will prevent even spacing of the text.
filial vs filial
Note: In OpenType, required ligatures are expected to be associated to the rlig feature. All other ligatures are therefore considered optional. In some cases, however, UA or platform heuristics apply additional ligatures in order to handle broken fonts; this specification does not define or override such exceptional handling.

Cursive Scripts

If it is able, the UA may apply letter spacing to [=cursive scripts=] by translating the total extra space to be distributed to a run of such letters into some form of cursive elongation (or compression, for negative tracking values) for that run that results in an equivalent total expansion (or compression) of the run. Otherwise, if the UA cannot expand text from a [=cursive script=] without breaking its cursive connections, it must not apply spacing between any pair of that script’s [=typographic letter units=] at all (effectively treating each word as a single [=typographic letter unit=] for the purpose of letter-spacing). Both cases will result in an effective spacing of zero between such letters; however the former will preserve the sense of stretching out the text.
Below are some appropriate and inappropriate examples of spacing out Arabic text.
Original text
BAD Even distribution of space between each letter. Notice this breaks cursive joins!
OK Distributing ∑letter-spacing by typographically-appropriate cursive elongation. The resulting text is as long as the previous evenly-spaced example.
OK Suppressing 'letter-spacing' between Arabic letters. Notice 'letter-spacing' is nonetheless applied to non-Arabic characters (like [=spaces=]).
BAD Applying 'letter-spacing' only between non-joined letters. This distorts typographic color and obfuscates word boundaries.
Note: Proper cursive elongation or compression of a text can vary depending on the script, typeface, language, location within a word, location within a line, implementation complexity, font capabilities, and calligraphic preferences, and may not be possible in certain cases at all. It may involve the use of shortening ligatures, swash variants, contextual forms, elongation glyphs such as U+0640 ـ ARABIC TATWEEL, or other microtypography. It is outside the scope of CSS to define rules for these effects. Authors should avoid applying 'letter-spacing' to cursive scripts unless they are prepared to accept non-interoperable results.

Shaping Across Element Boundaries

Text shaping must be broken at inline box boundaries when any of the following are true for any box whose boundary separates the two [=typographic character units=]: Text shaping must not be broken across inline box boundaries when there is no effective change in formatting, or if the only formatting changes do not affect the glyphs (as in applying text decoration). text-transform/text-transform-shaping-001.html text-transform/text-transform-shaping-002.html text-transform/text-transform-shaping-003.html shaping/shaping-000.html shaping/reference/shaping-000-ref.html shaping/shaping-004.html shaping/shaping-005.html shaping/shaping-006.html shaping/shaping-007.html shaping/shaping-014.html shaping/reference/shaping-014-ref.html shaping/shaping-016.html shaping/reference/shaping-016-ref.html shaping/shaping-022.html shaping/reference/shaping-022-ref.html shaping/shaping-025.html shaping/reference/shaping-025-ref.html shaping/shaping_lig-000.html boundary-shaping/boundary-shaping-001.html boundary-shaping/boundary-shaping-010.html Text shaping should not be broken across inline box boundaries otherwise, if it is reasonable and possible for that case given the limitations of the font technology. shaping/shaping-001.html shaping/reference/shaping-001-ref.html shaping/shaping-002.html shaping/reference/shaping-002-ref.html shaping/shaping-003.html shaping/reference/shaping-003-ref.html shaping/shaping-008.html shaping/reference/shaping-008-ref.html shaping/shaping-017.html shaping/shaping-018.html shaping/shaping-020.html shaping/reference/shaping-020-ref.html shaping/shaping-021.html shaping/reference/shaping-021-ref.html shaping/shaping-023.html shaping/reference/shaping-023-ref.html shaping/shaping-024.html shaping/reference/shaping-024-ref.html boundary-shaping/boundary-shaping-009.html
An example of reasonable and possible shaping across boundaries is Arabic shaping: in many systems this is performed by the font engine, allowing the font to provide variant glyphs with potentially very sophisticated contextual shaping. It’s not generally possible to rely on this system across a font change unless the font engine has an API to provide context, but it is straightforward and therefore quite reasonable for an engine to work around this limitation by, for example, using the zero-width-joiner (U+200D) or zero-width-non-joiner (U+200C) as appropriate to solicit the correct choice of initial/medial/final/isolated glyph. An example of possible but not reasonable shaping across boundaries is handling a font that is sensitive to 20 characters of context on either side to choose its glyphs: passing all the text before and after the string in question, even through multiple inline boundaries with formatting changes, is complicated. The UA could handle such cases, but is not required to, as they are not typical or fundamentally required by any modern writing system. An example of impossible shaping across boundaries is a change in font weight partway through the word “and” in a font where a ligature would replace all three letters of the word “and” with an ampersand glyph (“&”).

Edge Effects

Edge effects control the indentation of lines with respect to other lines in the block ('text-indent') and how content is measured at the start and end edges of a line ('hanging-punctuation').

First Line Indentation: the 'text-indent' property

	Name: text-indent
	Value: [ <> ] && hanging? && each-line?
	Initial: 0
	Applies to: block containers
	Inherited: yes
	Percentages: refers to block container’s own inline-axis inner size
	Computed value: computed <> value, plus any specified keywords
	Animation type: by computed value type
	Canonical order: per grammar
	
inheritance.html parsing/text-indent-valid.html parsing/text-indent-invalid.html parsing/text-indent-computed.html animations/text-indent-interpolation.html animations/text-indent-composition.html text-indent/text-indent-long-line-crash.html text-indent/anonymous-flex-item-001.html text-indent/anonymous-grid-item-001.html c547-indent-000.xht c547-indent-001.xht text-indent-012.xht text-indent-013.xht text-indent-014.xht text-indent-112.xht text-indent-applies-to-001.xht text-indent-applies-to-002.xht text-indent-applies-to-003.xht text-indent-applies-to-005.xht text-indent-applies-to-006.xht text-indent-applies-to-007.xht text-indent-applies-to-008.xht text-indent-applies-to-009.xht text-indent-applies-to-010.xht text-indent-applies-to-011.xht text-indent-applies-to-012.xht text-indent-applies-to-013.xht text-indent-applies-to-014.xht text-indent-applies-to-015.xht text-indent-inherited-001.xht This property specifies the indentation applied to lines of inline content in a block. The indent is treated as a margin applied to the start edge of the line box. text-indent-010.xht text-indent-012.xht text-indent-013.xht text-indent-115.xht text-indent-on-blank-line-rtl-left-align.html text-indent-overflow-001.xht text-indent-overflow-002.xht text-indent-overflow-003.xht text-indent-overflow-004.xht text-indent-rtl-001.xht text-indent-rtl-002.xht text-indent/text-indent-min-max-content-001.html text-indent/text-indent-overflow.html text-indent/text-indent-text-align-end.html Unless otherwise specified by the ''each-line'' and/or ''text-indent/hanging'' keywords, only lines that are the [=first formatted line=] of an element are affected. [[!CSS-PSEUDO-4]] For example, the first line of an anonymous block box is only affected if it is the first child of its parent element. text-indent-014.xht text-indent-wrap-001.xht text-indent/text-indent-with-absolute-pos-child.html Values have the following meanings:
<length>
Gives the amount of the indent as an absolute length. text-indent-004.xht text-indent-005.xht text-indent-006.xht text-indent-007.xht text-indent-008.xht text-indent-010.xht text-indent-012.xht text-indent-013.xht text-indent-014.xht text-indent-016.xht text-indent-017.xht text-indent-018.xht text-indent-019.xht text-indent-020.xht text-indent-028.xht text-indent-029.xht text-indent-030.xht text-indent-031.xht text-indent-032.xht text-indent-040.xht text-indent-041.xht text-indent-042.xht text-indent-043.xht text-indent-044.xht text-indent-052.xht text-indent-053.xht text-indent-054.xht text-indent-055.xht text-indent-056.xht text-indent-064.xht text-indent-065.xht text-indent-066.xht text-indent-067.xht text-indent-068.xht text-indent-076.xht text-indent-077.xht text-indent-078.xht text-indent-079.xht text-indent-080.xht text-indent-088.xht text-indent-089.xht text-indent-090.xht text-indent-091.xht text-indent-092.xht text-indent-109.xht text-indent-110.xht text-indent-111.xht text-indent-113.xht text-indent-114.xht text-indent-115.xht text-indent-intrinsic-001.xht text-indent-intrinsic-002.xht text-indent-intrinsic-003.xht text-indent-intrinsic-004.xht text-indent-on-blank-line-rtl-left-align.html text-indent-overflow-001.xht text-indent-overflow-002.xht text-indent-overflow-003.xht text-indent-overflow-004.xht text-indent-rtl-001.xht text-indent-rtl-002.xht text-indent/text-indent-length-001.html text-indent/text-indent-length-002.html text-indent/text-indent-overflow.html text-indent/text-indent-text-align-end.html
<percentage>
Gives the amount of the indent as a percentage of the block container’s own logical width. text-indent-011.xht text-indent-100.xht text-indent-101.xht text-indent-102.xht text-indent-103.xht text-indent-104.xht text-indent-percent-001.xht Percentages must be treated as ''0'' for the purpose of calculating [=intrinsic size contributions=], but are always resolved normally when performing layout. text-indent/percentage-value-intrinsic-size.html text-indent/text-indent-percentage-001.xht text-indent/text-indent-percentage-002.html text-indent/text-indent-percentage-003.html text-indent/text-indent-percentage-004.html Note: This can lead to the element overflowing. It is not recommended to use percentage indents and intrinsic sizing together.
each-line
Indentation affects the first line of each block container and each line after a forced line break (but not lines after a soft wrap break). text-indent/text-indent-each-line-hanging.html
hanging
Inverts which lines are affected. text-indent/text-indent-each-line-hanging.html

If 'text-align' is ''text-align/start'' and 'text-indent' is ''5em'' in left-to-right text with no floats present, then first line of text will start 5em into the block:

			     Since CSS1 it has been possible to
			indent the first line of a block element
			5em by setting the 'text-indent' property 
			to '5em'.
		
If we add the ''text-indent/hanging'' keyword, then the first line will start flush, but other lines will be indented 5em:
			In CSS3 we can instead indent all other
			     lines of the block element by 5em
			     by setting the 'text-indent' property
			     to 'hanging 5em'.
		
Since the 'text-indent' property only affects the “first formatted line”, a line after a forced break will not be indented.
			   For example, in the middle of
			this paragraph is an equation,
			which is centered:
			             x + y = z
			The first line after the equation
			is flush (else it would look like
			we started a new paragraph).
		
However, sometimes (as in poetry or code), it is appropriate to indent each line that happens to be long enough to wrap. In the following example, 'text-indent' is given a value of ''3em hanging each-line'', giving the third line of the poem a hanging indent where it soft-wraps at the block’s right boundary:
			In a short line of text
			There need be no wrapping,
			But when we go on and on and on  
			   and on,
			Sometimes a soft break
			Can help us stay on the page.
		
Note: Since the 'text-indent' property inherits, when specified on a block element, it will affect descendant inline-block elements. For this reason, it is often wise to specify ''text-indent: 0'' on elements that are specified ''display: inline-block''.

Hanging Glyphs

When a glyph at the start or end edge of a line hangs, it is not considered when measuring the line’s contents for fit, alignment, or justification. Depending on the line’s alignment/justification, this can result in the mark being placed outside the line box. The [=hanging=] glyph is also not taken into account when computing [=intrinsic sizes=] ([=min-content size=] and [=max-content size=]), and any sizes derived thereof. (The interaction of this measurement and kerning is currently UA-defined; the CSSWG welcomes advice on this point.) white-space/full-width-leading-spaces-004.html white-space/white-space-intrinsic-size-005.html white-space/white-space-intrinsic-size-006.html overflow-wrap/overflow-wrap-min-content-size-009.html A hanging glyph is still enclosed inside its parent inline box and still participates in text justification: its character advance is just not measured when determining how much content fits on the line, how much the line’s contents need to be expanded or compressed for justification, or how to position the content within the line box for text alignment. Effectively, the [=hanging=] glyph character advance is re-interpreted as an additional negative margin on the affected edge of its parent [=inline box=]; the line is otherwise laid out as usual. An overflowing [=hanging glyph=] should typically be considered [=ink overflow=] so as to avoid creating unnecessary scrollbars, but the UA may treat it as [=scrollable overflow=] when the content is editable or in other circumstances where treating it as [=scrollable overflow=] would be useful to the user. [[!CSS-OVERFLOW-3]] hanging-punctuation/hanging-scrollable-001.html white-space/white-space-intrinsic-size-019.html white-space/white-space-intrinsic-size-020.html hanging-punctuation/hanging-punctuation-block-bound-001.html hanging-punctuation/hanging-punctuation-inline-bound-001.html white-space/trailing-space-and-text-alignment-001.html white-space/trailing-space-and-text-alignment-003.html white-space/trailing-space-and-text-alignment-005.html white-space/trailing-space-and-text-alignment-rtl-001.html white-space/trailing-space-and-text-alignment-rtl-003.html white-space/trailing-space-and-text-alignment-rtl-005.html white-space/white-space-pre-wrap-trailing-spaces-021.html white-space/white-space-pre-wrap-trailing-spaces-022.html white-space/white-space-pre-wrap-trailing-spaces-023.html text-justify/text-justify-and-trailing-spaces-001.html text-justify/text-justify-and-trailing-spaces-002.html text-justify/text-justify-and-trailing-spaces-003.html text-justify/text-justify-and-trailing-spaces-004.html text-justify/text-justify-and-trailing-spaces-005.html text-justify/text-justify-and-trailing-spaces-006.html In some cases, a glyph at the end of a line can conditionally hang: it [=hangs=] only if it does not otherwise fit in the line prior to justification. It is not considered when measuring the line’s contents for fit; however, any part of it that does not fit is considered to [=hang=]. Glyphs that [=conditionally hang=] are not taken into account when computing [=min-content sizes=] and any sizes derived thereof, but they are taken into account for [=max-content sizes=] and any sizes derived thereof. white-space/white-space-intrinsic-size-013.html white-space/white-space-intrinsic-size-014.html white-space/white-space-intrinsic-size-017.html Non-zero inline-axis borders or padding between a [=hang=]able glyph and the edge of the line prevent the glyph from hanging. For example, a period at the end of an inline box with end padding does not [=hang=] at the end edge of a line. Multiple adjacent glyphs can hang together, however specific limits on how many are allowed to hang may be specified (e.g. at most one punctuation character may [=hang=] at each edge of the line).

Hanging Punctuation: the 'hanging-punctuation' property

	Name: hanging-punctuation
	Value: none | [ first || [ force-end | allow-end ] || last ]
	Initial: none
	Applies to: text
	Inherited: yes
	Canonical order: per grammar
	Computed value: specified keyword(s)
	Animation type: discrete
	
inheritance.html parsing/hanging-punctuation-valid.html parsing/hanging-punctuation-invalid.html hanging-punctuation/hanging-punctuation-inline-001.html This property determines whether a punctuation mark, if one is present, [=hangs=] and may be placed outside the line box (or in the indent) at the start or at the end of a line of text. Note: If there is not sufficient padding on the block container, 'hanging-punctuation' can trigger overflow.

Values have the following meanings:
none
No punctuation character is made to [=hang=].
first
An opening bracket, quote, or ideographic space at the start of the [=first formatted line=] of an element [=hangs=]. This applies to all characters in the Unicode categories Ps, Pf, Pi plus the ASCII quote marks U+0027 ' APOSTROPHE and U+0022 " QUOTATION MARK and the IDEOGRAPHIC SPACE U+3000. hanging-punctuation/hanging-punctuation-first-001.xht hanging-punctuation/hanging-punctuation-first-002.html
last
A closing bracket or quote at the end of the last formatted line of an element [=hangs=]. This applies to all characters in the Unicode categories Pe, Pf, Pi plus the ASCII quote marks U+0027 ' APOSTROPHE and U+0022 " QUOTATION MARK. hanging-punctuation/hanging-punctuation-last-001.xht
force-end
A [=stop or comma=] at the end of a line [=hangs=]. hanging-punctuation/hanging-punctuation-force-end-001.xht
allow-end
A [=stop or comma=] at the end of a line [=conditionally hangs=]. hanging-punctuation/hanging-punctuation-allow-end-001.xht
At most one punctuation character may [=hang=] at each edge of the line. Stops and commas allowed to [=hang=] include:
U+002C , COMMA
U+002E . FULL STOP
U+060C ، ARABIC COMMA
U+06D4 ۔ ARABIC FULL STOP
U+3001 IDEOGRAPHIC COMMA
U+3002 IDEOGRAPHIC FULL STOP
U+FF0C FULLWIDTH COMMA
U+FF0E FULLWIDTH FULL STOP
U+FE50 SMALL COMMA
U+FE51 SMALL IDEOGRAPHIC COMMA
U+FE52 SMALL FULL STOP
U+FF61 HALFWIDTH IDEOGRAPHIC FULL STOP
U+FF64 HALFWIDTH IDEOGRAPHIC COMMA
The UA may include other characters as appropriate. Note: The CSS Working Group would appreciate if UAs including other characters would inform the working group of such additions.
The ''hanging-punctuation/allow-end'' and ''force-end'' are two variations of hanging punctuation used in East Asia.
hanging-punctuation: allow-end
				p {
				  text-align: justify;
				  hanging-punctuation: allow-end;
				}
			
hanging-punctuation: force-end
				p {
				  text-align: justify;
				  hanging-punctuation: force-end;
				}
			
The punctuation at the end of the first line for ''hanging-punctuation/allow-end'' does not hang, because it fits without hanging. However, if ''force-end'' is used, it is forced to hang. The justification measures the line without the hanging punctuation. Therefore when the line is expanded, the punctuation is pushed outside the line.

Bidirectionality and Line Boxes

The start and end sides of a line box are determined by the [=inline base direction=] of the line box. Although they usually match, the [=inline base direction=] of a [=line box=] is distinct from the [=inline base direction=] of the [=containing block=] or the [=bidi paragraph=]. The [=line box=]’s [=inline base direction=] affects 'text-align-all', 'text-align-last', 'text-indent', and 'hanging-punctuation'-- i.e. the position and alignment of its contents with respect to its edges. It does not affect the formatting or ordering of inline content (which is controlled by the Unicode Bidirectional Algorithm as applied by CSS Writing Modes [[!UAX9]] [[CSS-WRITING-MODES-4]]). In most cases, a [=line box=]’s [=inline base direction=] is given by its [=containing block=]’s computed 'direction'. However, if its [=containing block=] has ''unicode-bidi: plaintext'' [[!CSS-WRITING-MODES-4]]:
In the following example, assuming the <block> is a start-aligned preformatted block (''display: block; white-space: pre; text-align: start''), every other line is right-aligned: <block style="unicode-bidi: plaintext"> français فارسی français فارسی français فارسی </block>
Because neutral characters (such as punctuation) and isolated runs are skipped when finding the inline base direction of a plaintext bidi paragraph, the line box in the following example will be left-to-right (and thus left-aligned given ''text-align: start''), as dictated by the first strong character, ‘h’: <para style="display: block; direction: rtl; unicode-bidi:plaintext"> “<quote style="unicode-bidi:plaintext">שלום!</quote>”, they said. </para>
<textarea style="direction: rtl; unicode-bidi:plaintext"> Hello! </textarea> Because of ''unicode-bidi: plaintext'', the “Hello!” is typeset LTR (i.e. with the exclamation mark on the right side) and left-aligned, ignoring the containing block’s RTL 'direction'. This makes the empty line following it LTR as well, which means that a caret on that line should appear at its left edge. The empty first line, however, is right-aligned: having no preceding line, it assumes the RTL direction of its containing block.

Appendix A: Text Processing Order of Operations

This appendix is normative. The following list defines the order of text operations. (Implementations are not bound to this order as long as the resulting layout is the same.)
  1. [[#white-space-phase-1|white space processing]] part I (pre-wrapping)
  2. [[#transforming|text transformation]]
  3. [[css-writing-modes-4#text-combine-upright|text combination]] [[!CSS-WRITING-MODES-4]]
  4. [[css-writing-modes-4#text-orientation|text orientation]] [[!CSS-WRITING-MODES-4]]
  5. [=wrapping|text wrapping=] while applying per line: * [[#text-indent-property|indentation]] * [[css-writing-modes-4#text-direction|bidirectional reordering]] [[!CSS2]] / [[!CSS-WRITING-MODES-4]] * [[#white-space-phase-2|white space processing]] part II * font/glyph selection and positioning [[!CSS-FONTS-3]] * 'letter-spacing' and 'word-spacing' * [[#hanging-punctuation-property|hanging punctuation]]
  6. [[#justification|justification]] (which may affect glyph selection and/or text wrapping, looping back into that step)
  7. [[#text-align-property|text alignment]]
letter-spacing/letter-spacing-bidi-003.xht

Appendix B: Conversion to Plaintext

This appendix is normative for the purpose of plaintext copy-paste operations. When a CSS-rendered document is converted to a plaintext format, it is expected that:

Appendix C: Default UA Stylesheet

This appendix is informative, and is to help UA developers to implement a default stylesheet for HTML, but UA developers are free to ignore or modify as appropriate.
			/* make option elements align together */
			option { text-align: match-parent; }
		

Appendix D: Scripts and Spacing

This appendix is normative. Typographic behavior varies somewhat by language, but varies drastically by writing system. This appendix categorizes some common [=Unicode script|scripts=] in Unicode 6.0 according to their justification and spacing behavior. Category descriptions are descriptive, not prescriptive; the determining factor is the prioritization of [=justification opportunities=].
block scripts
CJK and by extension all Wide characters (see East Asian Width [[!UAX11]]). The following [=Unicode scripts=] are included: Bopomofo, Han, Hangul, Hiragana, Katakana, and Yi. Characters of the [=East Asian Width property=] Wide and Fullwidth are also included, but Ambiguous characters are included only if the [=writing system=] is Chinese, Korean, or Japanese.
clustered scripts
Clustered scripts have discrete units and break only at word boundaries, but do not use visible word separators. They prioritize stretching spaces, but comfortably admit inter-character spacing for justification. The clustered scripts include, but are not limited to, the following [=Unicode scripts=]: Khmer, Lao, Myanmar, New Tai Lue, Tai Le, Tai Tham, Tai Viet, Thai
cursive scripts
Cursive scripts do not admit gaps between their letters for either justification or 'letter-spacing'. The following [=Unicode scripts=] are included: Arabic, Mandaic, Mongolian, N’Ko, Phags Pa, Syriac Note: Indic scripts with baseline connectors (such as Devanagari and Gujarati) are not considered [=cursive scripts=], and do admit such gaps between [=typographic character units=]. See Indic Layout Requirements. [[ILREQ]]
User agents should update this list as they update their Unicode support to handle as-yet-unencoded cursive scripts in future versions of Unicode, and are encouraged to ask the CSSWG to update this spec accordingly.

Appendix E: Characters and Properties

This appendix is normative. Unicode defines four code point-level properties that are referenced in CSS typesetting:
East Asian width property
Defined in Unicode Standard Annex #11 [[!UAX11]] and given as the East_Asian_Width property in the Unicode Character Database [[!UAX44]].
general category
Defined in Unicode Standard Annex #44 [[!UAX44]] and given as the General_Category property in the Unicode Character Database [[!UAX44]].
script property
Defined in Unicode Standard Annex #24 [[!UAX24]] and given as the Script property in the Unicode Character Database [[!UAX44]]. (UAs must include any ScriptExtensions.txt assignments in this mapping.)
Vertical Orientation
Defined in Unicode Standard Annex #50 [[!UAX50]] as the Vertical_Orientation property in the Unicode Character Database [[!UAX44]].
Unicode defines properties for individual code points, but sometimes it is necessary to determine the properties of a [=typographic character unit=]. For the purposes of CSS Text, the properties of a [=typographic character unit=] are given by the base character of its first [=grapheme cluster=]-- except in two cases:

Appendix F: Identifying the Content Writing System

This appendix is normative. While most languages have a preferred writing system, some have multiple, and most can also be transcribed into one or more foreign writing systems. As a common example, most languages have at least one Latin transcription, and can thus be written in the Latin writing system. Transcribed texts typically adopt the typographic conventions of the writing system: for example Japanese “romaji” and Chinese Pinyin use Latin letters and word spaces, and follow Latin line-breaking and justification practices accordingly. As another example, historical ideographic Korean (ko-Hani) does not use word spaces, and should therefore be typeset similar to Chinese rather than modern Korean. In HTML or any other [=document language=] using BCP47 tags for identifying languages to declare the [=content language=], authors can disambiguate or indicate the use of an atypical writing system with script subtags. [[BCP47]] For example, to indicate use of the Latin writing system for languages which don’t natively use it, the -Latn script subtag can be added, e.g. ja-Latn for Japanese romaji. Other subtags exist for other writing systems, see ISO’s Code for the Representation of Names of Scripts and the ISO15924 script tag registry. [[ISO15924]]
Some common/historical examples of using BCP47 tags with script subtags:
zh-Latn
Chinese, written in Latin transcription.
ko-Hani
Korean, written in Hanja (Chinese ideographic characters).
tr-Arab
Turkish, written in Arabic script.
mn-Cyrl
Mongolian, written in Cyrillic.
mn-Mong
Mongolian, written in traditional Mongolian script.
However, BCP47 script subtags are not typically used (and are in fact discouraged) for languages strongly associated with a single writing system: instead that writing system is expected to be implied when no other is specified. [[BCP47]] IANA maintains a database of various languages’ most common writing system via the Suppress-Script field in its language subtag registry for this purpose. Note: More advice on language tagging can be found in the Internationalization Working Group’s “Language tags in HTML and XML” and “Choosing a Language Tag”. When no writing system is explicitly indicated, UAs should assume the most common writing system of the declared [=content language=] for language-sensitive typographic behaviors such as line-breaking or justification. However, UAs must not assume that writing system if the author has explicitly declared a different one. If the UA has no language-specific knowledge of a particular language and writing system combination, it must use the typographic conventions of the declared writing system (assuming the conventions of a different language if necessary), not the conventions of the declared language in an assumed writing system, which would be inappropriate to the declared writing system. writing-system/writing-system-font-001.html writing-system/writing-system-text-transform-001.html writing-system/writing-system-segment-break-001.html writing-system/writing-system-line-break-001.html writing-system/writing-system-line-break-002.html The full correspondence between languages and their most common writing systems is out of scope for this document. However, user agents must assume at least the following:

Appendix G: Small Kana Mappings

This appendix is normative.
Small Kana Map to Full-size Kana
Small Full-size
ぁ U+3041 あ U+3042
ぃ U+3043 い U+3044
ぅ U+3045 う U+3046
ぇ U+3047 え U+3048
ぉ U+3049 お U+304A
ゕ U+3095 か U+304B
ゖ U+3096 け U+3051
𛄲 U+1B132 こ U+3053
っ U+3063 つ U+3064
ゃ U+3083 や U+3084
ゅ U+3085 ゆ U+3086
ょ U+3087 よ U+3088
ゎ U+308E わ U+308F
𛅐 U+1B150 ゐ U+3090
𛅑 U+1B151 ゑ U+3091
𛅒 U+1B152 を U+3092
ァ U+30A1 ア U+30A2
ィ U+30A3 イ U+30A4
ゥ U+30A5 ウ U+30A6
ェ U+30A7 エ U+30A8
ォ U+30A9 オ U+30AA
ヵ U+30F5 カ U+30AB
ㇰ U+31F0 ク U+30AF
ヶ U+30F6 ケ U+30B1
𛅕 U+1B155 コ U+30B3
ㇱ U+31F1 シ U+30B7
ㇲ U+31F2 ス U+30B9
ッ U+30C3 ツ U+30C4
ㇳ U+31F3 ト U+30C8
ㇴ U+31F4 ヌ U+30CC
ㇵ U+31F5 ハ U+30CF
ㇶ U+31F6 ヒ U+30D2
ㇷ U+31F7 フ U+30D5
ㇸ U+31F8 ヘ U+30D8
ㇹ U+31F9 ホ U+30DB
ㇺ U+31FA ム U+30E0
ャ U+30E3 ヤ U+30E4
ュ U+30E5 ユ U+30E6
ョ U+30E7 ヨ U+30E8
ㇻ U+31FB ラ U+30E9
ㇼ U+31FC リ U+30EA
ㇽ U+31FD ル U+30EB
ㇾ U+31FE レ U+30EC
ㇿ U+31FF ロ U+30ED
ヮ U+30EE ワ U+30EF
𛅤 U+1B164 ヰ U+30F0
𛅥 U+1B165 ヱ U+30F1
𛅦 U+1B166 ヲ U+30F2
𛅧 U+1B167 ン U+30F3
ァ U+FF67 ア U+FF71
ィ U+FF68 イ U+FF72
ゥ U+FF69 ウ U+FF73
ェ U+FF6A エ U+FF74
ォ U+FF6B オ U+FF75
ッ U+FF6F ツ U+FF82
ャ U+FF6C ヤ U+FF94
ュ U+FF6D ユ U+FF95
ョ U+FF6E ヨ U+FF96
text-transform/text-transform-full-size-kana-001.html text-transform/text-transform-full-size-kana-002.html text-transform/text-transform-full-size-kana-003.html text-transform/text-transform-full-size-kana-004.html text-transform/text-transform-full-size-kana-005.html text-transform/text-transform-full-size-kana-006.html text-transform/text-transform-full-size-kana-007.html text-transform/text-transform-full-size-kana-008.html

Privacy Considerations

This specification leaks the user’s installed hyphenation and line-breaking dictionaries.

Security Considerations

This specification introduces no new security considerations.

Acknowledgements

This specification would not have been possible without the help from: Addison Phillips, Aharon Lanin, Alan Stearns, Ambrose Li, Arnold Schrijver, Arye Gittelman, Ayman Aldahleh, Ben Errez, Bert Bos, Chris Lilley, Chris Pratley, Chris Thrasher, Chris Wilson, Dave Hyatt, David Baron, Emilio Cobos Álvarez, Eric LeVine, Etan Wexler, Frank Tang, Håkon Wium Lie, IM Mincheol, Ian Hickson, James Clark, Javier Fernandez, John Daggett, Jonathan Kew, Ken Lunde, Laurie Anna Edlund, Marcin Sawicki, Martin Dürst, Martin Heijdra, Masafumi Yabe, Masayasu Ishikawa, Michael Jochimsen, Michel Suignard, Mike Bemford, Myles Maxfield, Nat McCully, Paul Nelson, Rahul Sonnad, Richard Ishida, Shinyu Murakami, Stephen Deach, Steve Zilles, Takao Suzuki, Tantek Çelik, Xidorn Quan, Yaniv Feinberg.

Changes

Recent Changes

The following normative changes have been made since the September 2023 Candidate Recommendation: * None yet The following normative changes have been made since the February 2023 Candidate Recommendation. * Update [[#small-kana]] to Unicode 15.0. (Issue 8442) text-transform/text-transform-full-size-kana-008.html * Non-tailorable Unicode line breaking controls other than NBSP take precedence over our rule about atomic inlines. (Issue 8972)
For Web-compatibility there is a [=soft wrap opportunity=] before and after each replaced element or other [=atomic inline=], even when adjacent to a character that would normally suppress them, such asincluding U+00A0 NO-BREAK SPACE. However, with the exception of U+00A0 NO-BREAK SPACE, there must be no [=soft wrap opportunity=] between [=atomic inlines=] and adjacent characters belonging to the Unicode GL, WJ, or ZWJ line breaking classes. [[UAX14]]
line-breaking/line-breaking-atomic-003.html line-breaking/line-breaking-atomic-004.html line-breaking/line-breaking-atomic-005.html line-breaking/line-breaking-atomic-006.html line-breaking/line-breaking-replaced-002.html line-breaking/line-breaking-replaced-003.html line-breaking/line-breaking-atomic-010.html line-breaking/line-breaking-atomic-011.html line-breaking/line-breaking-atomic-012.html line-breaking/line-breaking-atomic-013.html line-breaking/line-breaking-atomic-014.html line-breaking/line-breaking-atomic-015.html line-breaking/line-breaking-atomic-016.html line-breaking/line-breaking-atomic-017.html line-breaking/line-breaking-atomic-018.html line-breaking/line-breaking-atomic-019.html line-breaking/line-breaking-atomic-020.html line-breaking/line-breaking-atomic-021.html line-breaking/line-breaking-atomic-022.html line-breaking/line-breaking-atomic-023.html line-breaking/line-breaking-atomic-024.html line-breaking/line-breaking-atomic-025.html line-breaking/line-breaking-atomic-026.html line-breaking/line-breaking-atomic-027.html The following normative changes have been made since the December 2020 Candidate Recommendation. * Allow ''hanging-punctuation: first'' to hang U+300 IDEOGRAPHIC SPACE in order to accommodate plaintext indentation habits. (Issue 2462)
first
An opening bracket, or quote, or ideographic space at the start of the [=first formatted line=] of an element [=hangs=]. This applies to all characters in the Unicode categories Ps, Pf, Pi plus the ASCII quote marks U+0027 ' APOSTROPHE and U+0022 " QUOTATION MARK plus the ASCII quote marks U+0027 ' APOSTROPHE and U+0022 " QUOTATION MARK and the IDEOGRAPHIC SPACE U+3000.
hanging-punctuation/hanging-punctuation-first-002.html * Define that ''distribute'' computes to ''inter-character'', rather than merely behave the same; allow ''text-justify/distribute'' to be implemented as a [=legacy value alias=], since this is easier for some engines and does not matter for compatibility. (Issue 6156, Issue 7322) parsing/text-justify-computed-legacy.html * Clarify that language-specific hyphenation rules also apply to explicit [=hyphenation opportunities=]. (Issue 5973)
Words are only hyphenated where there are characters inside the word that explicitly suggest [=hyphenation opportunities=]. The UA must use the appropriate language-specific hyphenation character(s) and should apply any appropriate spelling changes just as for automatic hyphenation at the same point.
hyphens/i18n/hyphens-i18n-manual-001.html hyphens/i18n/hyphens-i18n-manual-002.html hyphens/i18n/hyphens-i18n-manual-003.html hyphens/i18n/hyphens-i18n-manual-004.html hyphens/i18n/hyphens-i18n-manual-005.html * Define ''text-align/match-parent'' on the [=root element=] to compute to ''text-align/start'' instead of computing against the [=principal writing mode=]. (Issue 6542) text-align/text-align-match-parent-root-logical.html * Make authoring advice regarding 'text-transform' a normative recommendation. (Issue 8279)

Note: The 'text-transform' property only affects the presentation layer; correct casing for semantic purposes is expected to be represented in the source document.

Advisement: Authors must not rely on 'text-transform' for semantic purposes; rather the correct casing and semantics should be encoded in the source document text and markup.

In addition there have been some minor editorial fixes.

Older Changes

See also earlier list of changes covering the 2020 and 2019 Working Drafts prior to that Candidate Recommendation and the Disposition of Comments covering all comments between 2013 and 2020.