HTML and CSS Reference
Table C-1 (continued)
WCAG 2.0 Guidelines
1.2.8 Media Alternative (Prerecorded): An alternative for time-based media is provided
for all prerecorded synchronized media and for all prerecorded video-only media.
1.2.9 Audio-only (Live): An alternative for time-based media that presents equivalent
information for live audio-only content is provided.
Guideline 1.3 Adaptable: Create content that can be presented in different ways (for example
simpler layout) without losing information or structure.
1.3.1 Info and Relationships: Information, structure, and relationships conveyed through
presentation can be programmatically determined or are available in text.
1.3.2 Meaningful Sequence: When the sequence in which content is presented affects its
meaning, a correct reading sequence can be programmatically determined.
1.3.3 Sensory Characteristics: Instructions provided for understanding and operating
content do not rely solely on sensory characteristics of components such as shape, size,
visual location, orientation, or sound.
Guideline 1.4 Distinguishable: Make it easier for users to see and hear content including
separating foreground from background.
1.4.1 Use of Color: Color is not used as the only visual means of conveying information,
indicating an action, prompting a response, or distinguishing a visual element.
1.4.2 Audio Control: If any audio on a Web page plays automatically for more than
3 seconds, either a mechanism is available to pause or stop the audio, or a mechanism
is available to control the audio volume independently from the overall system volume level.
1.4.3 Contrast (Minimum): The visual presentation of text and images of text has a
contrast ratio of at least 4.5:1 (for specific exceptions, refer to w3.org/TR/WCAG).
1.4.4 Resize text: Except for captions and images of text, text can be resized without
assistive technology up to 200 percent without loss of content or functionality.
1.4.5 Images of Text: If the technologies being used can achieve the visual presentation,
text is used to convey information rather than images of (for specific exceptions, refer to
1.4.6 Contrast (Enhanced): The visual presentation of text and images of text has a
contrast ratio of at least 7:1 (for specific exceptions, refer to w3.org/TR/WCAG).
1.4.7 Low or No Background Audio: For prerecorded audio-only content in which
1) the audio does not contain background sounds, 2) the background sounds can be
turned off, or 3) the background sounds are at least 20 decibels lower than the foreground
1.4.8 Visual Presentation: For the visual presentation of blocks of text, a mechanism
is available to manipulate the look of the page (e.g., background colors, text size) easily.
1.4.9 Images of Text (No Exception): Images of text are only used for pure decoration or
where a particular presentation of text is essential to the information being conveyed.
Principle 2: Operable—User interface components and navigation must be operable.
Guideline 2.1 Keyboard Accessible: Make all functionality available from the keyboard.
2.1.1 Keyboard: All 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.
2.1.2 No Keyboard Trap: If 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.
2.1.3 Keyboard (No Exception): All functionality of the content is operable through
a keyboard interface without requiring specific timings for individual keystrokes.