All non-text content that is presented to the user has a text alternative that serves the equivalent purpose, except for the situations listed below.
- Controls, Input
If non-text content is a control or accepts user input, then it has a name that describes its purpose. (Refer to Success Criterion 4.1.2 for additional requirements for controls and content that accepts user input.) - Time-Based Media
If non-text content is time-based media, then text alternatives at least provide descriptive identification of the non-text content. (Refer to Guideline 1.2 for additional requirements for media.) - Test
If non-text content is a test or exercise that would be invalid if presented in text, then text alternatives at least provide descriptive identification of the non-text content. - Sensory
If non-text content is primarily intended to create a specific sensory experience, then text alternatives at least provide descriptive identification of the non-text content. - CAPTCHA
If the purpose of non-text content is to confirm that content is being accessed by a person rather than a computer, then text alternatives that identify and describe the purpose of the non-text content are provided, and alternative forms of CAPTCHA using output modes for different types of sensory perception are provided to accommodate different disabilities. - Decoration, Formatting, Invisible
If non-text content is pure decoration, is used only for visual formatting, or is not presented to users, then it is implemented in a way that it can be ignored by assistive technology.
For prerecorded audio-only and prerecorded video-only media, the following are true, except when the audio or video is a media alternative for text and is clearly labeled as such:
- Prerecorded Audio-only
An alternative for time-based media is provided that presents equivalent information for prerecorded audio-only content. - Prerecorded Video-only
Either an alternative for time-based media or an audio track is provided that presents equivalent information for prerecorded video-only content.
Information, structure, and relationships conveyed through presentation can be programmatically determined or are available in text.
Mehr lesenWhen the sequence in which content is presented affects its meaning, a correct reading sequence can be programmatically determined.
Mehr lesenInstructions provided for understanding and operating content do not rely solely on sensory characteristics of components such as shape, color, size, visual location, orientation, or sound.
Mehr lesenContent does not restrict its view and operation to a single display orientation, such as portrait or landscape, unless a specific display orientation is essential.
Mehr lesenIn content implemented using markup languages, the purpose of User Interface Components, icons, and regions can be programmatically determined.
Mehr lesenColor is not used as the only visual means of conveying information, indicating an action, prompting a response, or distinguishing a visual element.
Mehr lesenThe visual presentation of text and images of text has a contrast ratio of at least 4.5:1, except for the following:
- Large Text
Large-scale text and images of large-scale text have a contrast ratio of at least 3:1; - Incidental
Text or images of text that are part of an inactive user interface component, that are pure decoration, that are not visible to anyone, or that are part of a picture that contains significant other visual content, have no contrast requirement. - Logotypes
Text that is part of a logo or brand name has no contrast requirement.
Except for captions and images of text, text can be resized without assistive technology up to 200 percent without loss of content or functionality.
Mehr lesenIf the technologies being used can achieve the visual presentation, text is used to convey information rather than images of text except for the following:
- Customizable
The image of text can be visually customized to the user's requirements; - Essential
A particular presentation of text is essential to the information being conveyed.
The visual presentation of text and images of text has a contrast ratio of at least 7:1, except for the following:
- Large Text
Large-scale text and images of large-scale text have a contrast ratio of at least 4.5:1; - Incidental
Text or images of text that are part of an inactive user interface component, that are pure decoration, that are not visible to anyone, or that are part of a picture that contains significant other visual content, have no contrast requirement. - Logotypes
Text that is part of a logo or brand name has no contrast requirement.
Images of text are only used for pure decoration or where a particular presentation of text is essential to the information being conveyed.
Mehr lesenContent can be presented without loss of information or functionality, and without requiring scrolling in two dimensions for:
- Vertical scrolling content at a width equivalent to 320 CSS pixels;
- Horizontal scrolling content at a height equivalent to 256 CSS pixels.
Except for parts of the content which require two-dimensional layout for usage or meaning.
Mehr lesenThe visual presentation of the following have a contrast ratio of at least 3:1 against adjacent color(s):
- User Interface Components
Visual information required to identify user interface components and states, except for inactive components or where the appearance of the component is determined by the user agent and not modified by the author;
- Graphical Objects
Parts of graphics required to understand the content, except when a particular presentation of graphics is essential to the information being conveyed.
In content implemented using markup languages that support the following text style properties, no loss of content or functionality occurs by setting all of the following and by changing no other style property:
- Line height (line spacing) to at least 1.5 times the font size;
- Spacing following paragraphs to at least 2 times the font size;
- Letter spacing (tracking) to at least 0.12 times the font size;
- Word spacing to at least 0.16 times the font size.
Exception: Human languages and scripts that do not make use of one or more of these text style properties in written text can conform using only the properties that exist for that combination of language and script.
Mehr lesenWhere receiving and then removing pointer hover or keyboard focus triggers additional content to become visible and then hidden, the following are true:
- Dismissable
A mechanism is available to dismiss the additional content without moving pointer hover or keyboard focus, unless the additional content communicates an input error or does not obscure or replace other content;
- Hoverable
If pointer hover can trigger the additional content, then the pointer can be moved over the additional content without the additional content disappearing;
- Persistent
The additional content remains visible until the hover or focus trigger is removed, the user dismisses it, or its information is no longer valid.
Exception: The visual presentation of the additional content is controlled by the user agent and is not modified by the author.
Mehr lesenAll functionality of the content is operable through a keyboard interface without requiring specific timings for individual keystrokes, except where the underlying function requires input that depends on the path of the user's movement and not just the endpoints.
Mehr lesenIf keyboard focus can be moved to a component of the page using a keyboard interface, then focus can be moved away from that component using only a keyboard interface, and, if it requires more than unmodified arrow or tab keys or other standard exit methods, the user is advised of the method for moving focus away.
Mehr lesenFor each time limit that is set by the content, at least one of the following is true:
- Turn off
The user is allowed to turn off the time limit before encountering it; or - Adjust
The user is allowed to adjust the time limit before encountering it over a wide range that is at least ten times the length of the default setting; or - Extend
The user is warned before time expires and given at least 20 seconds to extend the time limit with a simple action (for example, "press the space bar"), and the user is allowed to extend the time limit at least ten times; or - Real-time Exception
The time limit is a required part of a real-time event (for example, an auction), and no alternative to the time limit is possible; or - Essential Exception
The time limit is essential and extending it would invalidate the activity; or - 20 Hour Exception
The time limit is longer than 20 hours.
For moving, blinking, scrolling, or auto-updating information, all of the following are true:
- Moving, blinking, scrolling
For any moving, blinking or scrolling information that (1) starts automatically, (2) lasts more than five seconds, and (3) is presented in parallel with other content, there is a mechanism for the user to pause, stop, or hide it unless the movement, blinking, or scrolling is part of an activity where it is essential; and - Auto-updating
For any auto-updating information that (1) starts automatically and (2) is presented in parallel with other content, there is a mechanism for the user to pause, stop, or hide it or to control the frequency of the update unless the auto-updating is part of an activity where it is essential.
Timing is not an essential part of the event or activity presented by the content, except for non-interactive synchronized media and real-time events.
Mehr lesenInterruptions can be postponed or suppressed by the user, except interruptions involving an emergency.
Mehr lesenWhen an authenticated session expires, the user can continue the activity without loss of data after re-authenticating.
Mehr lesenUsers are warned of the duration of any user inactivity that could cause data loss, unless the data is preserved for more than 20 hours when the user does not take any actions.
Mehr lesenWeb pages do not contain anything that flashes more than three times in any one second period, or the flash is below the general flash and red flash thresholds.
Mehr lesenWeb pages do not contain anything that flashes more than three times in any one second period.
Mehr lesenMotion animation triggered by interaction can be disabled, unless the animation is essential to the functionality or the information being conveyed.
Mehr lesenA mechanism is available to bypass blocks of content that are repeated on multiple Web pages.
Mehr lesenThe purpose of each link can be determined from the link text alone or from the link text together with its programmatically determined link context, except where the purpose of the link would be ambiguous to users in general.
Mehr lesenMore than one way is available to locate a Web page within a set of Web pages except where the Web Page is the result of, or a step in, a process.
Mehr lesenAny keyboard operable user interface has a mode of operation where the keyboard focus indicator is visible.
Mehr lesenA mechanism is available to allow the purpose of each link to be identified from link text alone, except where the purpose of the link would be ambiguous to users in general.
Mehr lesenAll functionality that uses multipoint or path-based gestures for operation can be operated with a single pointer without a path-based gesture, unless a multipoint or path-based gesture is essential.
Mehr lesenFor functionality that can be operated using a single pointer, at least one of the following is true:
- No Down-Event
The down-event of the pointer is not used to execute any part of the function; - Abort or Undo
Completion of the function is on the up-event, and a mechanism is available to abort the function before completion or to undo the function after completion; - Up Reversal
The up-event reverses any outcome of the preceding down-event; - Essential
Completing the function on the down-event is essential.
For user interface components with labels that include text or images of text, the name contains the text that is presented visually.
Mehr lesenFunctionality that can be operated by device motion or user motion can also be operated by user interface components and responding to the motion can be disabled to prevent accidental actuation, except when:
- Supported Interface
The motion is used to operate functionality through an accessibility supported interface; - Essential
The motion is essential for the function and doing so would invalidate the activity.
The size of the target for pointer inputs is at least 44 by 44 CSS pixels except when:
- Equivalent
The target is available through an equivalent link or control on the same page that is at least 44 by 44 CSS pixels; - Inline
The target is in a sentence or block of text; - User Agent Control
The size of the target is determined by the user agent and is not modified by the author; - Essential
A particular presentation of the target is essential to the information being conveyed.
Web content does not restrict use of input modalities available on a platform except where the restriction is essential, required to ensure the security of the content, or required to respect user settings.
Mehr lesenThe default human language of each Web page can be programmatically determined.
Mehr lesenThe 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.
Mehr lesenA mechanism is available for identifying specific definitions of words or phrases used in an unusual or restricted way, including idioms and jargon.
Mehr lesenA mechanism for identifying the expanded form or meaning of abbreviations is available.
Mehr lesenWhen any user interface component receives focus, it does not initiate a change of context.
Mehr lesenNavigational mechanisms that are repeated on multiple Web pages within a set of Web pages occur in the same relative order each time they are repeated, unless a change is initiated by the user.
Mehr lesenComponents that have the same functionality within a set of Web pages are identified consistently.
Mehr lesenIf an input error is automatically detected, the item that is in error is identified and the error is described to the user in text.
Mehr lesenFor Web pages that require the user to submit information, at least one of the following is true:
- Reversible
Submissions are reversible. - Checked
Data entered by the user is checked for input errors and the user is provided an opportunity to correct them. - Confirmed
A mechanism is available for reviewing, confirming, and correcting information before finalizing the submission.
In content implemented using markup languages, status messages can be programmatically determined through role or properties such that they can be presented to the user by assistive technologies without receiving focus.
Mehr lesen