Make text content readable and understandable
Content should be read not only by assistive technology, but also by users, who can experience or can’t experience it in many different ways: visual, auditory, both visual and auditory. Complex texts and content can be difficult to be read, both for the assistive technology, but also by users. So this guideline is intented to editors, to prepare the text in a so everybody can understand it.
Additional, Advisory Techniques
- Set expectations about content in the page from uncontrolled sources
- Provide sign language interpretation for all content
- Use the clearest and simplest language appropriate for the content
- Avoid centrally aligned text
- Avoid text that is fully justified (to both left and right margins) in a way that causes
poor spacing between words or characters - Use left-justified text for languages that are written left to right and right-justified
text for languages that are written right-to-left - Limit text column width
- Avoid chunks of italic text
- Avoid overuse of different styles on individual pages and in sites
- Make links visually distinct
- Use images, illustrations, video, audio, or symbols to clarify meaning
- Provide practical examples to clarify content
- Use a light pastel background rather than a white background behind black text
- Avoid the use of unique interface controls unnecessarily
- Use upper and lower case according to the spelling rules of the text language
- Avoid unusual foreign words
- Provide sign language versions of information, ideas, and processes that must be
understood in order to use the content - Make any reference to a location in a Web page into a link to that location
- Make references to a heading or title include the full text of the title
- Provide easy-to-read versions of basic information about a set of Web pages, including
information about how to contact the Webmaster - Provide a sign language version of basic information about a set of Web pages,
including information about how to contact the Webmaster
Criterion 3.1.1 Language of Page
The default human language of each Web page can be programmatically determined.
How to. Mandatory techniques
- Identify default human language(s) using language attributes on the html element
Additional, Advisory Techniques
- Specifying the default language in the HTTP header
- Use http or the Content-Language meta tag for metadata
Criterion 3.1.2 Language of Parts
The human language of each passage or phrase in the content can be programmatically determined except for proper names, technical terms, words of indeterminate language, and words or phrases that have become part of the vernacular of the immediately surrounding text.
How to. Mandatory techniques
- Identify changes in human languages using language attributes to identify changes in the human language
Additional, Advisory Techniques
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Make text that is not in the default human language of the Web page visually distinct
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Give the names of any languages used in foreign passages or phrases
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Provide language markup on proper names to facilitate correct pronunciation by screen readers
Criterion 3.1.3 Unusual Words
A mechanism is available for identifying specific definitions of words or phrases used in an unusual or restricted way, including idioms and jargon.
How to. Mandatory techniques
- Provide the definition of a word or phrase used in an unusual or restricted way for the first occurrence of the word or phrase in a Web page by linking to definitions (use definition lists or the link element to link to a glossary ) or using inline definitions (use the dfn element to identify the defining instance of a word)
- Provide the definition of a word or phrase used in an unusual or restricted way for each occurrence of the word or phrase in a Web page by linking to definitions (use definition lists or the link element to link to a glossary), providing a glossary or a function to search an online dictionary
- Provide the definition of a word or phrase used in an unusual or restricted way for each occurrence of the word or phrase in a Web page by linking to definitions (use definition lists or the the link element to link to a glossary) or using inline definitions (use the dfn element to identify the defining instance of a word)
- Use markup and visual formatting to help users recognize words that have special meaning
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Provide a voice-enabled dictionary search so that users who have difficulty typing or spelling can speak the word whose definition they need
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Provide a sign language dictionary to help users who are deaf find the necessary definitions
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Provide a mechanism for finding definitions for all words in text content
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Provide a mechanism to determine the meaning of each word or phrase in text content
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Avoid unusual foreign words
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Use a series of dictionaries in cascading fashion to provide meanings
If the word or phrase has a unique meaning within the Web page
If the word or phrase means different things within the same Web page
Additional, Advisory Techniques
Criterion 3.1.4 Abbreviations
A mechanism for identifying the expanded form or meaning of abbreviations is available.
How to. Mandatory techniques
If the abbreviation has only one meaning within the Web page:
- Provide the expansion or explanation of an abbreviation for the first occurrence of the abbreviation in a Web page by providing the abbreviation immediately following the expanded form, linking to definitions or using the abbr and acronym elements
- Provide the expansion or explanation of an abbreviation for all occurrences of the abbreviation in a Web page by linking to definitions, using the link element to link to a glossary, or providing a glossary, a function to search an online dictionary or definitions for abbreviations by using the abbr and acronym elements
If the abbreviation means different things within the same Web page
- Provide the expansion or explanation of an abbreviation for all occurrences of abbreviations in a Web pagel inking to definitions or using the abbr and acronym elements
Additional, Advisory Techniques
- Use unique abbreviations in a Web page
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Use visual formatting to help users recognize abbreviations
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Provide access to a talking dictionary to support users who might have difficulty decoding written definitions
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Provide a voice-enabled dictionary search so that users who have difficulty typing or spelling can speak the word whose definition they need
Criterion 3.1.5 Reading Level
When text requires reading ability more advanced than the lower secondary education level after removal of proper names and titles; supplemental content (or a version that does not require reading ability more advanced than the lower secondary education level) is available.
How to. Mandatory techniques
- Provide a text summary that requires reading ability less advanced than the upper secondary education level
- Provide visual illustrations, pictures, and symbols to help explain ideas, events, and processes
- Provide a spoken version of the text
- Make the text easier to read
- Provide sign language versions of information, ideas, and processes that must be understood in order to use the content
Additional, Advisory Techniques
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Provide text for navigational and landing pages that requires reading ability that is less advanced than the lower secondary education level
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Provide text for interior pages that requires reading ability at the lower secondary education level
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Include content summaries in metadata
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Use the clearest and simplest language appropriate for the content
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Use RDF to associate supplements with primary content
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Provide a clear representational image on the site’s home page
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Clearly mark, by use of text or icon, content which has been optimized for easy reading
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Use sentences that contain no redundant words, that is, words that do not change the meaning of the sentence
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Use sentences that contain no more than two conjunctions
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Use sentences that are no longer than the typical accepted length for secondary education (Note: In English that is 25 words)
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Use sentences that do not contain complex words or phrases that could be replaced with more commonly used words without changing the meaning of the sentence
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Provide summaries for different sections of text
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Use metadata to associate alternatives at different reading levels.
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Use the Dublin Core accessibility element to associate text content with text, graphical, or spoken supplements
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Use the ISO AfA accessibility element to associate text content with text, graphical, or spoken supplements
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Use the IMS accessibility element to associate text content with text, graphical, or spoken supplements
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Make metadata viewable by humans
Criterion 3.1.6 Pronunciation
A mechanism is available for identifying specific pronunciation of words where meaning of the words, in context, is ambiguous without knowing the pronunciation.
How to. Mandatory techniques
- Provide the pronunciation immediately following the word
- Link to pronunciations
- Provide a glossary that includes pronunciation information for words that have a unique pronunciation in the content and have meaning that depends on pronunciation
- Provide pronunciation information using the ruby element or standard diacritical marks that can be turned off
Additional, Advisory Techniques
- Providing pronunciations in a sound file, so that users can listen to the pronunciations of the word
- Providing a mechanism for finding pronunciations for all foreign words in text content
- Providing a mechanism to determine the pronunciations of each word or phrase in text content
More info
- Understanding Guideline 3.1 Readable
- Understanding Success Criterion 3.1.1 [Language of Page]
- Understanding Success Criterion 3.1.2 [Language of Parts]
- Understanding Success Criterion 3.1.3 [Unusual Words]
- Understanding Success Criterion 3.1.4 [Abbreviations]
- Understanding Success Criterion 3.1.5 [Reading Level]
- Understanding Success Criterion 3.1.6 [Pronunciation]
Link Summary
- http://www.w3.org/TR/UNDERSTANDING-WCAG20/meaning.html
- http://www.w3.org/TR/UNDERSTANDING-WCAG20/meaning-doc-lang-id.html
- http://www.w3.org/TR/UNDERSTANDING-WCAG20/meaning-other-lang-id.html
- http://www.w3.org/TR/UNDERSTANDING-WCAG20/meaning-idioms.html
- http://www.w3.org/TR/UNDERSTANDING-WCAG20/meaning-located.html
- http://www.w3.org/TR/UNDERSTANDING-WCAG20/meaning-supplements.html
- http://www.w3.org/TR/UNDERSTANDING-WCAG20/meaning-pronunciation.html




