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WCAG 2.1 Standard: Summary

This page lists all the Success Criteria of the W3C Web Content Accessibility Guidelines, version 2.1 ("WCAG 2.1"). (Original document)

This standard is also known since October 2012 as the international standard ISO/IEC 40500:2012. Further, WCAG 2.1 is currently being considered as the baseline for web (and some non-web) documents in two proposed procurement standards: the refresh of the U.S. Section 508 standard, and the European Commission's Standardisation Mandate M376 (Phase 2). For compliance against these proposals, you should use Level AA of the WCAG 2.1 standard.

Anything that is not marked as an Error should be manually tested:

Keep in mind when you read these success criteria, that any claim of conformance must meet the Conformance Requirements, of which meeting a certain level of conformance (eg. meeting all of the applicable Success Criteria for the target level and lower) is merely one. Other things to keep in mind:

Principle 1: Perceivable

Guideline 1.1: Text Alternatives

Provide text alternatives for any non-text content so that it can be changed into other forms people need, such as large print, braille, speech, symbols or simpler language.

Success Criterion A AA AAA Message Name Applies To Techniques
SC 1.1.1: Non-text Content (Level A)

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 Guideline 4.1 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.
ErrorErrorError

Img element is the only content of the link, but is missing alt text. The alt text should describe the purpose of the link.

[Standard].Principle1.Guideline1_1.1_1_1.H30.2

Image elements with an absent or empty alt attribute, that is the only non-blank content of a link.

ErrorErrorError

Img element missing an alt attribute. Use the alt attribute to specify a short text alternative.

[Standard].Principle1.Guideline1_1.1_1_1.H37

Image element (outside of a link) that is completely missing an alt attribute.

ErrorErrorError

Img element with empty alt text must have absent or empty title attribute.

[Standard].Principle1.Guideline1_1.1_1_1.H67.1

Image element (outside of a link) that is marked with an empty alt attribute (intending it to be ignored), but has a non-empty title attribute.

WarningWarningWarning

Img element is marked so that it is ignored by Assistive Technology.

[Standard].Principle1.Guideline1_1.1_1_1.H67.2

Image element (outside of a link) that is marked with an empty alt attribute, and its title attribute is empty or absent.

NoticeNoticeNotice

Ensure that the img element's alt text serves the same purpose and presents the same information as the image.

[Standard].Principle1.Guideline1_1.1_1_1.G94.Image

Images with alt text, in general.

ErrorErrorError

Image submit button missing an alt attribute. Specify a text alternative that describes the button's function, using the alt attribute

[Standard].Principle1.Guideline1_1.1_1_1.H36

Image submit button that has a missing or empty alt attribute.

NoticeNoticeNotice

Ensure that the image submit button's alt text identifies the purpose of the button.

[Standard].Principle1.Guideline1_1.1_1_1.G94.Button

Image submit buttons in general. In the case of these, they should describe the function of the button, not necessarily the image in general (although they should be the same).

ErrorErrorError

Area element in an image map missing an alt attribute. Each area element must have a text alternative that describes the function of the image map area.

[Standard].Principle1.Guideline1_1.1_1_1.H24

Area elements in an image map that have an empty or missing alt attribute.

NoticeNoticeNotice

Ensure that the area element's text alternative serves the same purpose as the part of image map image it references.

[Standard].Principle1.Guideline1_1.1_1_1.H24.2

Area elements with alt text, in general.

NoticeNoticeNotice

If this image cannot be fully described in a short text alternative, ensure a long text alternative is also available, such as in the body text or through a link.

[Standard].Principle1.Guideline1_1.1_1_1.G73,G74

Images with alt text, in general. Images such as graphs may need a long description; it is emitted as a Notice due to inability to check that one exists for sure (since it may be just part of body text, for example).

ErrorErrorError

Img element inside a link must not use alt text that duplicates the text content of the link.

[Standard].Principle1.Guideline1_1.1_1_1.H2.EG5

Image inside a link along with text content, where the alt attribute duplicates the text content (after trimming). Incorrect resolution of this technique.

ErrorErrorError

Img element inside a link has empty or missing alt text when a link beside it contains link text. Consider combining the links.

[Standard].Principle1.Guideline1_1.1_1_1.H2.EG4

As described in error message. Incorrect resolution of this technique.

ErrorErrorError

Img element inside a link must not use alt text that duplicates the content of a text link beside it.

[Standard].Principle1.Guideline1_1.1_1_1.H2.EG3

Image inside a link, that is next to a link that has the same text content (after trimming). "Next to" means the only thing between them is whitespace.

ErrorErrorError

Object elements must contain a text alternative after all other alternatives are exhausted.

[Standard].Principle1.Guideline1_1.1_1_1.H53

Object element (or group of nested object elements) that does not contain a text alternative at the deepest level. Message will fire on the innermost Object element.

NoticeNoticeNotice

Check that short (and if appropriate, long) text alternatives are available for non-text content that serve the same purpose and present the same information.

[Standard].Principle1.Guideline1_1.1_1_1.G94,G92.Object

Object elements (with a correctly specified text alternative) in general.

ErrorErrorError

Applet elements must contain a text alternative in the element's body, for browsers without support for the applet element.

[Standard].Principle1.Guideline1_1.1_1_1.H35.3

Applet element without a body text alternative.

ErrorErrorError

Applet elements must contain an alt attribute, to provide a text alternative to browsers supporting the element but are unable to load the applet.

[Standard].Principle1.Guideline1_1.1_1_1.H35.2

Applet element without an altt attribute.

NoticeNoticeNotice

Check that short (and if appropriate, long) text alternatives are available for non-text content that serve the same purpose and present the same information.

[Standard].Principle1.Guideline1_1.1_1_1.G94,G92.Applet

Applet elements (with correctly specified text alternatives) in general.

Guideline 1.2: Time-based Media

Provide alternatives for time-based media.

Success Criterion A AA AAA Message Name Applies To Techniques
SC 1.2.1: Audio-only and Video-only (Prerecorded) (Level A)

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.
NoticeNoticeNotice

If this embedded object contains pre-recorded audio only, and is not provided as an alternative for text content, check that an alternative text version is available.

[Standard].Principle1.Guideline1_2.1_2_1.G158

Elements which may contain audio.

NoticeNoticeNotice

If this embedded object contains pre-recorded video only, and is not provided as an alternative for text content, check that an alternative text version is available, or an audio track is provided that presents equivalent information.

[Standard].Principle1.Guideline1_2.1_2_1.G159,G166

Elements which may contain video.

SC 1.2.2: Captions (Prerecorded) (Level A)

Captions are provided for all prerecorded audio content in synchronized media, except when the media is a media alternative for text and is clearly labeled as such.

NoticeNoticeNotice

If this embedded object contains pre-recorded synchronised media and is not provided as an alternative for text content, check that captions are provided for audio content.

[Standard].Principle1.Guideline1_2.1_2_2.G87,G93

Elements which may contain synchronised media.

SC 1.2.3: Audio Description or Media Alternative (Prerecorded) (Level A)

An alternative for time-based media or audio description of the prerecorded video content is provided for synchronized media, except when the media is a media alternative for text and is clearly labeled as such.

Editor's Note: Superseded at level AAA by both Success Criterion 1.2.5 and Success Criterion 1.2.8. Superseded at level AA by Success Criterion 1.2.5. Implementing these would satisfy this Success Criterion automatically.

Notice

If this embedded object contains pre-recorded synchronised media and is not provided as an alternative for text content, check that an audio description of its video, and/or an alternative text version of the content is provided.

[Standard].Principle1.Guideline1_2.1_2_3.G69,G78,G173,G8

Elements which may contain synchronised media.

SC 1.2.4: Captions (Live) (Level AA)

Captions are provided for all live audio content in synchronized media.

NoticeNotice

If this embedded object contains synchronised media, check that captions are provided for live audio content.

[Standard].Principle1.Guideline1_2.1_2_4.G9,G87,G93

Elements which may contain synchronised media.

SC 1.2.5: Audio Description (Prerecorded) (Level AA)

Audio description is provided for all prerecorded video content in synchronized media.

NoticeNotice

If this embedded object contains pre-recorded synchronised media, check that an audio description is provided for its video content.

[Standard].Principle1.Guideline1_2.1_2_5.G78,G173,G8

Elements which may contain synchronised media.

SC 1.2.6: Sign Language (Prerecorded) (Level AAA)

Sign language interpretation is provided for all prerecorded audio content in synchronized media.

Notice

If this embedded object contains pre-recorded synchronised media, check that a sign language interpretation is provided for its audio.

[Standard].Principle1.Guideline1_2.1_2_6.G54,G81

Elements which may contain synchronised media.

SC 1.2.7: Extended Audio Description (Prerecorded) (Level AAA)

Where pauses in foreground audio are insufficient to allow audio descriptions to convey the sense of the video, extended audio description is provided for all prerecorded video content in synchronized media.

Notice

If this embedded object contains synchronised media, and where pauses in foreground audio is not sufficient to allow audio descriptions to convey the sense of pre-recorded video, check that an extended audio description is provided, either through scripting or an alternate version.

[Standard].Principle1.Guideline1_2.1_2_7.G8

Elements which may contain synchronised media.

SC 1.2.8: Media Alternative (Prerecorded) (Level AAA)

An alternative for time-based media is provided for all prerecorded synchronized media and for all prerecorded video-only media.

Notice

If this embedded object contains pre-recorded synchronised media or video-only content, check that an alternative text version of the content is provided.

[Standard].Principle1.Guideline1_2.1_2_8.G69,G159

Elements which may contain synchronised media.

SC 1.2.9: Audio-only (Live) (Level AAA)

An alternative for time-based media that presents equivalent information for live audio-only content is provided.

Notice

If this embedded object contains live audio-only content, check that an alternative text version of the content is provided.

[Standard].Principle1.Guideline1_2.1_2_9.G150,G151,G157

Elements which may contain audio.

Guideline 1.3: Adaptable

Create content that can be presented in different ways (for example simpler layout) without losing information or structure.

Success Criterion A AA AAA Message Name Applies To Techniques
SC 1.3.1: Info and Relationships (Level A)

Information, structure, and relationships conveyed through presentation can be programmatically determined or are available in text.

ErrorErrorError

Heading tag found with no content. Text that is not intended as a heading should not be marked up with heading tags.

[Standard].Principle1.Guideline1_3.1_3_1.H42.2

Heading element (h1-h6) that has no content. Non-breaking spaces are included in definition of "no content" in this case.

ErrorErrorError

Multiple labels exist with the same "for" attribute. If these labels refer to different form controls, the controls should have unique "id" attributes.

[Standard].Principle1.Guideline1_3.1_3_1.H93

Second and subsequent sightings of a specific value for the "for" attribute. Labels should be unique per element.

ErrorErrorError

This label's "for" attribute contains an ID that does not exist in the document.

[Standard].Principle1.Guideline1_3.1_3_1.H44.NonExistent

Label with a "for" attribute that does not match any ID used in the document.

WarningWarningWarning

This label's "for" attribute contains an ID that does not exist in the document fragment.

[Standard].Principle1.Guideline1_3.1_3_1.H44.NonExistentFragment

Label with a "for" attribute that does not match any ID used in the document fragment. This is does not

ErrorErrorError

This label's "for" attribute contains an ID that points to an element that is not a form control.

[Standard].Principle1.Guideline1_3.1_3_1.H44.NotFormControl

Label with a "for" attribute that matches an ID of an element that is not a form control (that should have a label). Specifically tested are input, select and textarea elements. Labels can only be associated with form controls, not generically with other elements.

ErrorErrorError

Label found without a "for" attribute, and therefore not explicitly associated with a form control.

[Standard].Principle1.Guideline1_3.1_3_1.H44.NoForAttr

Label without a "for" attribute. This means it could be being used implicitly (ie. wrapped around the field), or for some other purposes without an association with a field at all.

ErrorErrorError

Form control does not have an ID, therefore it cannot have an explicit label.

[Standard].Principle1.Guideline1_3.1_3_1.H44.NoId

Form control without an ID.

ErrorErrorError

Form control without a label contains an empty title attribute. The title attribute should identify the purpose of the control.

[Standard].Principle1.Guideline1_3.1_3_1.H65.3

Form control with no label, and has a title attribute (which it should have if no label) - but the title attribute is empty.

WarningWarningWarning

Check that the title attribute identifies the purpose of the control, and that a label element is not appropriate.

[Standard].Principle1.Guideline1_3.1_3_1.H65

Form control with a validly specified title attribute (no label). Title attributes are meant to only be used where the visual design does not permit the inclusion of a visible label.

ErrorErrorError

Form control does not have an explicit label or title attribute, identifying the purpose of the control.

[Standard].Principle1.Guideline1_3.1_3_1.H44.2

Form control with an ID that can be used to associate a label with, but has no explicit label or title attribute.

ErrorErrorError

Label element should not be used for this type of form control.

[Standard].Principle1.Guideline1_3.1_3_1.H44.NoLabelAllowed

Form controls which do not require a label, yet one has been provided. Button and hidden elements fall into this category - buttons have a label already (the text on the button), while the latter makes no sense.

ErrorErrorError

The label element for this control should be placed after this element.

[Standard].Principle1.Guideline1_3.1_3_1.H44.1.After

Form control where the label should be placed after the element, but not. Radio and checkbox inputs fall into this category.

ErrorErrorError

The label element for this control should be placed before this element.

[Standard].Principle1.Guideline1_3.1_3_1.H44.1.Before

Form control where the label should be placed before the element, but not. Textbox based inputs fall into this category (including text, textarea, password, file upload, ...)..

WarningWarningWarning

Semantic markup should be used to mark emphasised or special text so that it can be programmatically determined.

[Standard].Principle1.Guideline1_3.1_3_1.H49.[NodeName]

Element that is used for presentational purposes (by HTML 4's standards). The element code contains a title-cased version of the offending node name, to allow separate resolutions for each type of element (eg. B with STRONG).

WarningWarningWarning

Semantic markup should be used to mark emphasised or special text so that it can be programmatically determined.

[Standard].Principle1.Guideline1_3.1_3_1.H49.AlignAttr

Element with a align attribute. It should use CSS (text-align in text-related elements like paragraphs, or float with image floating).

WarningWarningWarning

Heading markup should be used if this content is intended as a heading.

[Standard].Principle1.Guideline1_3.1_3_1.H42

Paragraph of text that appears to have bold or italic content (whether through b/i or strong/em) as its only child.

ErrorErrorError

Table cell has an invalid scope attribute. Valid values are row, col, rowgroup, or colgroup.

[Standard].Principle1.Guideline1_3.1_3_1.H63.3

TH element with an invalid scope attribute.

WarningWarningWarning

Scope attributes on td elements that act as headers for other elements are obsolete in HTML5. Use a th element instead.

[Standard].Principle1.Guideline1_3.1_3_1.H63.2

TD element with a scope attribute. This is legal in HTML 4 but obsolete in HTML 5.

WarningWarningWarning

Scope attributes on th elements are ambiguous in a table with multiple levels of headings. Use the headers attribute on td elements instead.

[Standard].Principle1.Guideline1_3.1_3_1.H43.ScopeAmbiguous

Table with multiple levels of row or column headers, but using scope attribute. In this case, the headers attribute MUST be used; scope is not sufficient.

ErrorErrorError

Incorrect headers attribute on this td element. Expected "[expected headers]" but found "[actual headers]"

[Standard].Principle1.Guideline1_3.1_3_1.H43.IncorrectAttr

TD element with a headers attribute which does not match the one expected from its relevant header cells (the IDs of the TH elements it is aligned with). The test ignores extra white space, and the headers can be in any order, as long as they are there.

ErrorErrorError

The relationship between td elements and their associated th elements is not defined. As this table has multiple levels of th elements, you must use the headers attribute on td elements.

[Standard].Principle1.Guideline1_3.1_3_1.H43.HeadersRequired

Table with multiple levels of row or column headers, not using headers attributes at all.

ErrorErrorError

Not all th elements in this table contain an id attribute. These cells should contain ids so that they may be referenced by td elements headers attributes.'

[Standard].Principle1.Guideline1_3.1_3_1.H43.MissingHeaderIds

Table where not all TH elements contain IDs.

ErrorErrorError

Not all td elements in this table contain a headers attribute. Each headers attribute should list the ids of all th elements associated with that cell.

[Standard].Principle1.Guideline1_3.1_3_1.H43.MissingHeadersAttrs

Table where not all TD elements contain headers attributes (but some do).

ErrorErrorError

The relationship between td elements and their associated th elements is not defined. Use either the scope attribute on th elements, or the headers attribute on td elements.

[Standard].Principle1.Guideline1_3.1_3_1.H43,H63

Table with a single levels of row AND column headers, not using headers or scope attributes at all. (Either is acceptable in this situation.)

ErrorErrorError

Not all th elements in this table have a scope attribute. These cells should contain a scope attribute to identify their association with td elements.

[Standard].Principle1.Guideline1_3.1_3_1.H63.1

Table where some TH elements contain scope attributes - signifying an intention to use that format of association (and it's allowed) - but not all of them do.

ErrorErrorError

If this table is a data table, and both a summary attribute and a caption element are present, the summary should not duplicate the caption.

[Standard].Principle1.Guideline1_3.1_3_1.H39,H73.4

Table where the summary attribute and caption element match exactly (after trimming).

NoticeNoticeNotice

If this table is a data table, check that the summary attribute describes the tables organization or explains how to use the table.'

[Standard].Principle1.Guideline1_3.1_3_1.H73.3.Check

Table with specified summary attribute.

WarningWarningWarning

If this table is a data table, consider using the summary attribute of the table element to give an overview of this table.

[Standard].Principle1.Guideline1_3.1_3_1.H73.3.NoSummary

Table without summary attribute.

NoticeNoticeNotice

If this table is a data table, check that the caption element accurately describes this table.

[Standard].Principle1.Guideline1_3.1_3_1.H39.3.Check

Table with specified caption element.

WarningWarningWarning

If this table is a data table, consider using a caption element to the table element to identify this table.

[Standard].Principle1.Guideline1_3.1_3_1.H39.3.NoCaption

Table without caption element.

ErrorErrorError

Fieldset does not contain a legend element. All fieldsets should contain a legend element that describes a description of the field group.

[Standard].Principle1.Guideline1_3.1_3_1.H71.3

Fieldset without legend element.

WarningWarningWarning

If this selection list contains groups of related options, they should be grouped with optgroup.

[Standard].Principle1.Guideline1_3.1_3_1.H85.2

Select element not using optgroups. Use of optgroup may or may not be necessary, hence defined as a warning.

ErrorErrorError

Radio buttons or check boxes with the same name attribute must be contained within a fieldset element.

[Standard].Principle1.Guideline1_3.1_3_1.H71.2

Radio or checkbox inputs with the same name attribute, signifying they are part of a group, but with no fieldset marking them up as such.

WarningWarningWarning

Content appears to have the visual appearance of a bulleted list. It may be appropriate to mark this content up using a ul element.

[Standard].Principle1.Guideline1_3.1_3_1.H48.1

Paragraph content appearing like a bulleted list in text.

WarningWarningWarning

Content appears to have the visual appearance of a numbered list. It may be appropriate to mark this content up using an ol element.

[Standard].Principle1.Guideline1_3.1_3_1.H48.2

Paragraph content appearing like a numbered list in text.

WarningWarningError

The heading structure is not logically nested. This [heading] element (should be a [correct heading] to be properly nested / appears to be the primary document heading, so should be an h1 element).

[Standard].Principle1.Guideline1_3.1_3_1.G141

Header elements when a skip of a heading level is detected - for example, H2 followed by H4. Error at AAA level, as violation of Success Criterion 2.4.10.

WarningWarningWarning

If this element contains a navigation section, it is recommended that it be marked up as a list.

[Standard].Principle1.Guideline1_3.1_3_1.H48

P or DIV element that has more than one link.

SC 1.3.2: Meaningful Sequence (Level A)

When the sequence in which content is presented affects its meaning, a correct reading sequence can be programmatically determined.

NoticeNoticeNotice

Check that the content is ordered in a meaningful sequence when linearised, such as when style sheets are disabled.

[Standard].Principle1.Guideline1_3.1_3_2.G57

Top element.

SC 1.3.3: Sensory Characteristics (Level A)

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.

Note: For requirements related to color, refer to Guideline 1.4.

NoticeNoticeNotice

Where instructions are provided for understanding the content, do not rely on sensory characteristics alone (such as shape, size or location) to describe objects.

[Standard].Principle1.Guideline1_3.1_3_3.G96

Top element.

SC 1.3.4: Orientation (Level AA)

Content does not restrict its view and operation to a single display orientation, such as portrait or landscape, unless a specific display orientation is essential.

Note: For requirements related to color, refer to Guideline 1.4.

NoticeNotice

Check that content does not restrict its view and operation to a single display orientation, such as portrait or landscape, unless a specific display orientation is essential.

Top element.

  • N/A
SC 1.3.5: Identify Input Purpose (Level AA)

The purpose of each input field collecting information about the user can be programmatically determined when:

  • The input field serves a purpose identified in the Input Purposes for User Interface Components section; and
  • The content is implemented using technologies with support for identifying the expected meaning for form input data.
NoticeNotice

Check that the input field serves a purpose identified in the Input Purposes for User Interface Components section; and that the content is implemented using technologies with support for identifying the expected meaning for form input data.

Top element.

  • H98
NoticeNotice

This element does not have an autocomplete attribute. If this field collects information about the user, consider adding one to comply with this Success Criterion.

Input/select/textarea elements without an autocomplete attribute, where type is not one of: "hidden", "checkbox", "radio", "file", "submit", "image", "reset", "button".

  • H98
WarningWarning

Invalid autocomplete value: (value). Element does not belong to (name of control group) control group. See https://www.w3.org/TR/html52/sec-forms.html#autofilling-form-controls-the-autocomplete-attribute

Elements with an autocomplete attribute.

  • H98
WarningWarning

This element contains a potentially faulty value in its autocomplete attribute: (attribute value). See https://www.w3.org/TR/html52/sec-forms.html#autofilling-form-controls-the-autocomplete-attribute.

Elements with an autocomplete attribute.

  • H98
SC 1.3.6: Identify Purpose (Level AAA)

In content implemented using markup languages, the purpose of User Interface Components, icons, and regions can be programmatically determined.

Notice

Check that the purpose of User Interface Components, icons, and regions can be programmatically determined.

Top element.

  • ARIA11

Guideline 1.4: Distinguishable

Make it easier for users to see and hear content including separating foreground from background.

Success Criterion A AA AAA Message Name Applies To Techniques
SC 1.4.1: Use of Colour (Level A)

Colour is not used as the only visual means of conveying information, indicating an action, prompting a response, or distinguishing a visual element.

Note: This success criterion addresses colour perception specifically. Other forms of perception are covered in Guideline 1.3 including programmatic access to colour and other visual presentation coding.

NoticeNoticeNotice

Check that any information conveyed using colour alone is also available in text, or through other visual cues.

[Standard].Principle1.Guideline1_4.1_4_1.G14,G182

Top element.

SC 1.4.2: Audio Control (Level A)

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 audio volume independently from the overall system volume level.

Note: Since any content that does not meet this success criterion can interfere with a user's ability to use the whole page, all content on the Web page (whether or not it is used to meet other success criteria) must meet this success criterion. See Conformance Requirement 5: Non-Interference.

NoticeNoticeNotice

If any audio plays automatically for longer than 3 seconds, check that there is the ability to pause, stop or mute the audio.

[Standard].Principle1.Guideline1_4.1_4_2.F23

Top element.

SC 1.4.3: Contrast (Minimum) (Level AA)

The 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 minimum contrast requirement.

Editor's Note: Superseded by Success Criterion 1.4.6 at level AAA, which is a stricter application of the same concept.

Error

This element has insufficient contrast at this conformance level. Expected a contrast ratio of at least 4.5:1, but text in this element has a contrast ratio of {value}. Recommendation: {colour recommendations}.

[Standard].Principle1.Guideline1_4.1_4_3.G18

Elements with text with colours that have insufficient colour contrast for Level AA's requirements. The recommendation will contain a suggestion as to a colour change(s) that will satisfy the Success Criterion.

Error

This element has insufficient contrast at this conformance level. Expected a contrast ratio of at least 3:1, but text in this element has a contrast ratio of {value}. Recommendation: {colour recommendations}.

[Standard].Principle1.Guideline1_4.1_4_3.G145

Elements with text with colours that have insufficient colour contrast for the Level AA's requirements for "large text". The recommendation will contain a suggestion as to a colour change(s) that will satisfy the Success Criterion.

Warning

This element's text is placed on a background image. Ensure the contrast ratio between the text and all covered parts of the image are at least 4.5:1.

[Standard].Principle1.Guideline1_4.1_4_3.G18

Text placed in front of a background image. Applies at Level AA to general text.

Warning

This element's text is placed on a background image. Ensure the contrast ratio between the text and all covered parts of the image are at least 3:1.

[Standard].Principle1.Guideline1_4.1_4_3.G145

Text placed in front of a background image. Applies at Level AA to text defined as "large text".

WarningWarning

Check that this element has an inherited foreground colour to complement the corresponding inline background colour or image.

[Standard].Principle1.Guideline1_4.1_4_3.F24.BGColour

Elements with a background style or bgcolor attribute, without a corresponding foreground color style or attribute.

WarningWarning

Check that this element has an inherited background colour or image to complement the corresponding inline foreground colour.

[Standard].Principle1.Guideline1_4.1_4_3.F24.FGColour

Elements with a foreground color style or attribute, without a corresponding background color style or bgcolor attribute.

SC 1.4.4: Resize Text (Level AA)

Except for captions and images of text, text can be resized without assistive technology up to 2.1 percent without loss of content or functionality.

Editor's Note: Superseded by Success Criterion 1.4.8 at level AAA. That Success Criterion contains additional requirements when text is resized to 2.1%.

Notice

Check that text can be resized without assistive technology up to 2.1 percent without loss of content or functionality.

[Standard].Principle1.Guideline1_4.1_4_4.G142

Top element.

SC 1.4.5: Images of Text (Level AA)

If 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.

Note: Logotypes (text that is part of a logo or brand name) are considered essential.

Editor's Note: Superseded by Success Criterion 1.4.9 at level AAA, which removes most of the exceptions.

Notice

If the technologies being used can achieve the visual presentation, check that text is used to convey information rather than images of text, except when the image of text is essential to the information being conveyed, or can be visually customised to the user's requirements.

[Standard].Principle1.Guideline1_4.1_4_5.G140,C22,C30.AALevel

Top element.

SC 1.4.6: Contrast (Enhanced) (Level AAA)

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 minimum contrast requirement.
Error

This element has insufficient contrast at this conformance level. Expected a contrast ratio of at least 7:1, but text in this element has a contrast ratio of {value}. Recommendation: {colour recommendations}.

[Standard].Principle1.Guideline1_4.1_4_6.G17

Elements with text with colours that have insufficient colour contrast for Level AAA's requirements. The recommendation will contain a suggestion as to a colour change(s) that will satisfy the Success Criterion.

Error

This element has insufficient contrast at this conformance level. Expected a contrast ratio of at least 4.5:1, but text in this element has a contrast ratio of {value}. Recommendation: {colour recommendations}.

[Standard].Principle1.Guideline1_4.1_4_6.G18

Elements with text with colours that have insufficient colour contrast for the Level AAA's requirements for "large text". The recommendation will contain a suggestion as to a colour change(s) that will satisfy the Success Criterion.

Warning

This element's text is placed on a background image. Ensure the contrast ratio between the text and all covered parts of the image are at least 7:1.

[Standard].Principle1.Guideline1_4.1_4_6.G17

Text placed in front of a background image. Applies at Level AAA to general text.

Warning

This element's text is placed on a background image. Ensure the contrast ratio between the text and all covered parts of the image are at least 4.5:1.

[Standard].Principle1.Guideline1_4.1_4_6.G18

Text placed in front of a background image. Applies at Level AAA to text defined as "large text".

SC 1.4.7: Low or No Background Audio (Level AAA)

For prerecorded audio-only content that (1) contains primarily speech in the foreground, (2) is not an audio CAPTCHA or audio logo, and (3) is not vocalization intended to be primarily musical expression such as singing or rapping, at least one of the following is true:

  • No Background: The audio does not contain background sounds.
  • Turn Off: The background sounds can be turned off.
  • 20 dB: The background sounds are at least 20 decibels lower than the foreground speech content, with the exception of occasional sounds that last for only one or two seconds.

Note: Per the definition of "decibel," background sound that meets this requirement will be approximately four times quieter than the foreground speech content.

Editor's Note: The note may be confusing (as normally a 3 dB increase in power in anything, such as signal strength, is a 2x increase), but psychoacoustic models suggest a 10x increase in sound pressure (hence, 10 dB) is required for a 2x increase in loudness.

Notice

For pre-recorded audio-only content that is primarily speech (such as narration), any background sounds should be muteable, or be at least 20 dB (or about 4 times) quieter than the speech.

[Standard].Principle1.Guideline1_4.1_4_7.G56

Top element.

SC 1.4.8: Visual Presentation (Level AAA)

For the visual presentation of blocks of text, a mechanism is available to achieve the following:

  • Foreground and background colors can be selected by the user.
  • Width is no more than 80 characters or glyphs (40 if CJK).
  • Text is not justified (aligned to both the left and the right margins).
  • Line spacing (leading) is at least space-and-a-half within paragraphs, and paragraph spacing is at least 1.5 times larger than the line spacing.
  • Text can be resized without assistive technology up to 2.1 percent in a way that does not require the user to scroll horizontally to read a line of text on a full-screen window.
Notice

Check that a mechanism is available for the user to select foreground and background colours for blocks of text, either through the Web page or the browser.

[Standard].Principle1.Guideline1_4.1_4_8.G148,G156,G175

Top element.

Notice

Check that a mechanism exists to reduce the width of a block of text to no more than 80 characters (or 40 in Chinese, Japanese or Korean script).

[Standard].Principle1.Guideline1_4.1_4_8.H87,C20

Top element.

Notice

Check that blocks of text are not fully justified - that is, to both left and right edges - or a mechanism exists to remove full justification.

[Standard].Principle1.Guideline1_4.1_4_8.C19,G172,G169

Top element.

Notice

Check that line spacing in blocks of text are at least 150% in paragraphs, and paragraph spacing is at least 1.5 times the line spacing, or that a mechanism is available to achieve this.

[Standard].Principle1.Guideline1_4.1_4_8.G188,C21

Top element.

Notice

Check that text can be resized without assistive technology up to 2.1 percent without requiring the user to scroll horizontally on a full-screen window.

[Standard].Principle1.Guideline1_4.1_4_8.H87,G146,C26

Top element.

SC 1.4.9: Images of Text (No Exception) (Level AAA)

Images of text are only used for pure decoration or where a particular presentation of text is essential to the information being conveyed.

Note: Logotypes (text that is part of a logo or brand name) are considered essential.

Notice

Check that images of text are only used for pure decoration or where a particular presentation of text is essential to the information being conveyed.

[Standard].Principle1.Guideline1_4.1_4_9.G140,C22,C30.NoException

Top element.

SC 1.4.10: Reflow (Level AA)

Content 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.

NoticeNotice

Check that content 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.

Top element.

  • C31
  • C32
  • C33
  • C38
  • SCR34
  • G206
WarningWarning

This element has "position: fixed". This may require scrolling in two dimensions, which is considered a failure of this Success Criterion.

Any element with position:fixed.

  • C31
  • C32
  • C33
  • C38
  • SCR34
  • G206
WarningWarning

Preformatted text may require scrolling in two dimensions, which is considered a failure of this Success Criterion.

<pre> elements

  • C31
  • C32
  • C33
  • C38
  • SCR34
  • G206
WarningWarning

Interfering with a user agent's ability to zoom may be a failure of this Success Criterion.

Meta elements with maximum-scale, minimum-scale, user-scalable="0", or user-scalable="no"

  • C31
  • C32
  • C33
  • C38
  • SCR34
  • G206
SC 1.4.11: Non-text Contrast (Level AA)

The 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.

NoticeNotice

Check that the 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.

Top element.

  • G195
  • G207
  • G18
  • G145
  • G1744
  • F78
SC 1.4.12: Text Spacing (Level AA)

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.

NoticeNotice

Check that 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.

Top element.

  • C36
  • C35
SC 1.4.13: Content on Hover or Focus (Level AA)

Where 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.
NoticeNotice

Check that where 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.

Top element.

  • F95

Principle 2: Operable

Guideline 2.1: Keyboard Accessible

Make all functionality available from a keyboard.

Success Criterion A AA AAA Message Name Applies To Techniques
SC 2.1.1: Keyboard (Level A)

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.

Note 1: This exception relates to the underlying function, not the input technique. For example, if using handwriting to enter text, the input technique (handwriting) requires path-dependent input but the underlying function (text input) does not.
Note 2: This does not forbid and should not discourage providing mouse input or other input methods in addition to keyboard operation.

Editor's Note: Technically superseded by Success Criterion 2.1.3 at level AAA. To avoid redundancy, keyboard-related warnings will appear to come from Success Criterion 2.1.1 regardless of level.

WarningWarningWarning

Ensure the functionality provided by double-clicking on this element is available through the keyboard.

[Standard].Principle2.Guideline2_1.2_1_1.SCR20.DblClick

Elements with an inline ondblclick attribute.

WarningWarningWarning

Ensure the functionality provided by mousing over this element is available through the keyboard; for instance, using the focus event.

[Standard].Principle2.Guideline2_1.2_1_1.SCR20.MouseOver

Elements with an inline onmouseover attribute.

WarningWarningWarning

Ensure the functionality provided by mousing out of this element is available through the keyboard; for instance, using the blur event.

[Standard].Principle2.Guideline2_1.2_1_1.SCR20.MouseOut

Elements with an inline onmouseout attribute.

WarningWarningWarning

Ensure the functionality provided by moving the mouse on this element is available through the keyboard.

[Standard].Principle2.Guideline2_1.2_1_1.SCR20.MouseMove

Elements with an inline onmousemove attribute.

WarningWarningWarning

Ensure the functionality provided by mousing down on this element is available through the keyboard; for instance, using the keydown event.

[Standard].Principle2.Guideline2_1.2_1_1.SCR20.MouseDown

Elements with an inline onmousedown attribute.

WarningWarningWarning

Ensure the functionality provided by mousing up on this element is available through the keyboard; for instance, using the keyup event.

[Standard].Principle2.Guideline2_1.2_1_1.SCR20.MouseUp

Elements with an inline onmouseup attribute.

SC 2.1.2: No Keyboard Trap (Level A)

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.

Note: Since any content that does not meet this success criterion can interfere with a user's ability to use the whole page, all content on the Web page (whether or not it is used to meet other success criteria) must meet this success criterion. See Conformance Requirement 5: Non-Interference.

WarningWarningWarning

Check that this applet or plugin provides the ability to move the focus away from itself when using the keyboard.

[Standard].Principle2.Guideline2_1.2_1_2.F10

Applet or object elements.

SC 2.1.3: Keyboard (No Exception) (Level AAA)

All functionality of the content is operable through a keyboard interface without requiring specific timings for individual keystrokes.

Editor's Note: No additional techniques are provided over and above Success Criterion 2.1.1. Instead, if analogue, time-dependent input is required, the content simply cannot meet AAA conformance.

No tests for this Success Criterion.
SC 2.1.4: Character Key Shortcuts (Level A)

if a keyboard shortcut is implemented in content using only letter (including upper- and lower-case letters), punctuation, number, or symbol characters, then at least one of the following is true:

  • Turn off: A mechanism is available to turn the shortcut off;
  • Remap: A mechanism is available to remap the shortcut to use one or more non-printable keyboard characters (e.g. Ctrl, Alt, etc);
  • Active only on focus: The keyboard shortcut for a user interface component is only active when that component has focus.
NoticeNoticeNotice Check that if a keyboard shortcut is implemented in content using only letter (including upper- and lower-case letters), punctuation, number, or symbol characters, then at least one of the following is true:
  • Turn off: A mechanism is available to turn the shortcut off;
  • Remap: A mechanism is available to remap the shortcut to use one or more non-printable keyboard characters (e.g. Ctrl, Alt, etc);
  • Active only on focus: The keyboard shortcut for a user interface component is only active when that component has focus.

    Top element

    • N/A

    Guideline 2.2: Enough Time

    Provide users enough time to read and use content.

    Success Criterion A AA AAA Message Name Applies To Techniques
    SC 2.2.1: Timing Adjustable (Level A)

    For 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.

    Note: This success criterion helps ensure that users can complete tasks without unexpected changes in content or context that are a result of a time limit. This success criterion should be considered in conjunction with Success Criterion 3.2.1, which puts limits on changes of content or context as a result of user action.

    ErrorErrorError

    Meta refresh tag used to redirect to another page, with a time limit that is not zero. Users cannot control this time limit.

    [Standard].Principle2.Guideline2_2.2_2_1.F40.2

    Meta refresh element with a timeout greater than zero (with a URL to redirect to).

    ErrorErrorError

    Meta refresh tag used to refresh the current page. Users cannot control the time limit for this refresh.

    [Standard].Principle2.Guideline2_2.2_2_1.F41.2

    Meta refresh element with a timeout greater than zero (and no URL, indicating "refresh the current URL").

    SC 2.2.2: Pause, Stop, Hide (Level A)

    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.

    *Note 1: For requirements related to flickering or flashing content, refer to Guideline 2.3.
    *Note 2: Since any content that does not meet this success criterion can interfere with a user's ability to use the whole page, all content on the Web page (whether or not it is used to meet other success criteria) must meet this success criterion. See Conformance Requirement 5: Non-Interference.
    *Note 3: Content that is updated periodically by software or that is streamed to the user agent is not required to preserve or present information that is generated or received between the initiation of the pause and resuming presentation, as this may not be technically possible, and in many situations could be misleading to do so.
    *Note 4: An animation that occurs as part of a preload phase or similar situation can be considered essential if interaction cannot occur during that phase for all users and if not indicating progress could confuse users or cause them to think that content was frozen or broken.

    NoticeNoticeNotice

    If any part of the content moves, scrolls or blinks for more than 5 seconds, or auto-updates, check that there is a mechanism available to pause, stop, or hide the content.

    [Standard].Principle2.Guideline2_2.2_2_2.SCR33,SCR22,G187,G152,G186,G191

    Top element.

    WarningWarningWarning

    Ensure there is a mechanism available to stop this blinking element in less than five seconds.

    [Standard].Principle2.Guideline2_2.2_2_2.F4

    Elements that have a blink style (text-decoration: blink). There must be some method (via scripting, for example) to be able to turn these off within 5 seconds.

    ErrorErrorError

    Blink elements cannot satisfy the requirement that blinking information can be stopped within five seconds.

    [Standard].Principle2.Guideline2_2.2_2_2.F47

    Blink elements, in general.

    SC 2.2.3: No Timing (Level AAA)

    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.

    Notice

    Check that 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.

    [Standard].Principle2.Guideline2_2.2_2_3.G5

    Top element.

    SC 2.2.4: Interruptions (Level AAA)

    Interruptions can be postponed or suppressed by the user, except interruptions involving an emergency.

    Notice

    Check that all interruptions (including updates to content) can be postponed or suppressed by the user, except interruptions involving an emergency.

    [Standard].Principle2.Guideline2_2.2_2_4.SCR14

    Top element.

    SC 2.2.5: Re-authenticating (Level AAA)

    When an authenticated session expires, the user can continue the activity without loss of data after re-authenticating.

    Notice

    If this Web page is part of a set of Web pages with an inactivity time limit, check that an authenticated user can continue the activity without loss of data after re-authenticating.

    [Standard].Principle2.Guideline2_2.2_2_5.G105,G181

    Top element.

    SC 2.2.6: Timeouts (Level AAA)

    Users 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.

    Notice

    Check that users 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.

    Top element.

    • N/A

    Guideline 2.3: Seizures

    Do not design content in a way that is known to cause seizures.

    Success Criterion A AA AAA Message Name Applies To Techniques
    SC 2.3.1: Three Flashes or Below Threshold (Level A)

    Web 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.

    Note: Since any content that does not meet this success criterion can interfere with a user's ability to use the whole page, all content on the Web page (whether or not it is used to meet other success criteria) must meet this success criterion. See Conformance Requirement 5: Non-Interference.

    Editor's Note: Superseded by Success Criterion 2.3.2 at level AAA. That Success Criterion removes the flash threshold allowances.

    NoticeNotice

    Check that no component of the content flashes more than three times in any 1-second period, or that the size of any flashing area is sufficiently small.

    [Standard].Principle2.Guideline2_3.2_3_1.G19,G176

    Top element.

    SC 2.3.2: Three Flashes (Level AAA)

    Web pages do not contain anything that flashes more than three times in any one second period.

    Notice

    Check that no component of the content flashes more than three times in any 1-second period.

    [Standard].Principle2.Guideline2_3.2_3_2.G19

    Top element.

    SC 2.3.3: Animation from Interactions (Level AAA)

    Motion animation triggered by interaction can be disabled, unless the animation is essential to the functionality or the information being conveyed.

    Notice

    Check that motion animation triggered by interaction can be disabled, unless the animation is essential to the functionality or the information being conveyed.

    Top element.

    • C39

    Guideline 2.4: Navigable

    Provide ways to help users navigate, find content, and determine where they are.

    Success Criterion A AA AAA Message Name Applies To Techniques
    SC 2.4.1: Bypass Blocks (Level A)

    A mechanism is available to bypass blocks of content that are repeated on multiple Web pages.

    ErrorErrorError

    Iframe element requires a non-empty title attribute that identifies the frame.

    [Standard].Principle2.Guideline2_4.2_4_1.H64.1

    Iframe elements that have missing or empty title attribute.

    NoticeNoticeNotice

    Check that the title attribute of this element contains text that identifies the frame.

    [Standard].Principle2.Guideline2_4.2_4_1.H64.2

    Top element.

    NoticeNoticeNotice

    Ensure that any common navigation elements can be bypassed; for instance, by use of skip links, header elements, or ARIA landmark roles.

    [Standard].Principle2.Guideline2_4.2_4_1.G1,G123,G124,H69

    Top element. (No sufficient technique currently exists for ARIA landmark roles, but they are becoming increasingly supported.)

    ErrorErrorError

    This link points to a named anchor "[link target]" within the document, but no anchor exists with that name.

    [Standard].Principle2.Guideline2_4.2_4_1.G1,G123,G124.NoSuchId

    Anchor (a) or area element with a href element pointing to an anchor in the same document, such as "#content", but where that anchor - defined through an ID (anywhere), or a name attribute on an "a" attribute - does not exist. Applies to full documents.

    WarningWarningWarning

    This link points to a named anchor "[link target]" within the document, but no anchor exists with that name in the fragment tested.

    [Standard].Principle2.Guideline2_4.2_4_1.G1,G123,G124.NoSuchIdFragment2.4.2

    Anchor (a) or area element with a href element pointing to an ID in the same document, such as "#content", but where that anchor - defined through an ID (anywhere), or a name attribute on an "a" attribute - does not exist. Applies to document fragments: such a message is non-authoritative, as it depends on the document around it.

    SC 2.4.2: Page Titled (Level A)

    Web pages have titles that describe topic or purpose.

    ErrorErrorError

    A title should be provided for the document, using a non-empty title element in the head section.

    [Standard].Principle2.Guideline2_4.2_4_2.H25.1.NoTitleEl

    Document with a head section, but missing a title attribute.

    ErrorErrorError

    The title element in the head section should be non-empty.

    [Standard].Principle2.Guideline2_4.2_4_2.H25.1.EmptyTitle

    Title element that exists, but is empty.

    NoticeNoticeNotice

    Check that the title element describes the document.

    [Standard].Principle2.Guideline2_4.2_4_2.H25.2

    Top element.

    SC 2.4.3: Focus Order (Level A)

    If a Web page can be navigated sequentially and the navigation sequences affect meaning or operation, focusable components receive focus in an order that preserves meaning and operability.

    NoticeNoticeNotice

    If tabindex is used, check that the tab order specified by the tabindex attributes follows relationships in the content.

    [Standard].Principle2.Guideline2_4.2_4_3.H4.2

    Top element, when it is detected that tabindex has been used. Where tabindex has been inconsistently used, the order may not be correct.

    SC 2.4.4: Link Purpose (In Context) (Level A)

    The 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.

    Editor's Note: Superseded by Success Criterion 2.4.9 at AAA level, which removes the link context.

    NoticeNotice

    Check that the link text combined with programmatically determined link context, or its title attribute, identifies the purpose of the link.

    [Standard].Principle2.Guideline2_4.2_4_4.H77,H78,H79,H80,H81,H33

    Anchor (A) elements in general, where they contain a title attribute.

    NoticeNotice

    Check that the link text combined with programmatically determined link context identifies the purpose of the link.

    [Standard].Principle2.Guideline2_4.2_4_4.H77,H78,H79,H80,H81

    Anchor (A) elements in general (no title attribute).

    SC 2.4.5: Multiple Ways (Level AA)

    More 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.

    NoticeNotice

    If this Web page is not part of a linear process, check that there is more than one way of locating this Web page within a set of Web pages.

    [Standard].Principle2.Guideline2_4.2_4_5.G125,G64,G63,G161,G126,G185

    Top element.

    SC 2.4.6: Headings and Labels (Level AA)

    Headings and labels describe topic or purpose.

    NoticeNotice

    Check that headings and labels describe topic or purpose.

    [Standard].Principle2.Guideline2_4.2_4_6.G130,G131

    Top element.

    SC 2.4.7: Focus Visible (Level AA)

    Any keyboard operable user interface has a mode of operation where the keyboard focus indicator is visible.

    NoticeNotice

    Check that there is at least one mode of operation where the keyboard focus indicator can be visually located on user interface controls.

    [Standard].Principle2.Guideline2_4.2_4_7.G149,G165,G195,C15,SCR31

    Top element.

    SC 2.4.8: Location (Level AAA)

    Information about the user's location within a set of Web pages is available.

    Error

    Link elements can only be located in the head section of the document.

    [Standard].Principle2.Guideline2_4.2_4_8.H59.1

    Link element placed outside the head element of the document.

    Error

    Link element is missing a non-empty rel attribute identifying the link type.

    [Standard].Principle2.Guideline2_4.2_4_8.H59.2a

    Link element with missing or empty rel attribute.

    Error

    Link element is missing a non-empty href attribute pointing to the resource being linked.

    [Standard].Principle2.Guideline2_4.2_4_8.H59.2b

    Link element with missing or empty href attribute.

    SC 2.4.9: Link Purpose (Link Only) (Level AAA)

    A 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.

    Notice

    Check that text of the link describes the purpose of the link.

    [Standard].Principle2.Guideline2_4.2_4_9.H30

    Anchor (A) elements in general.

    SC 2.4.10: Section Headings (Level AAA)

    Section headings are used to organize the content.

    Note 1: "Heading" is used in its general sense and includes titles and other ways to add a heading to different types of content.
    Note 2: This success criterion covers sections within writing, not user interface components. User Interface components are covered under Success Criterion 4.1.2.

    Editor's Note: No specific test file provided. Where HTML is used, testing for relevant semantic headers (h1-h6) occurs in Success Criterion 1.3.1 - incorrect heading nesting results in an error at AAA level.

    No tests for this Success Criterion.

    Guideline 2.5: Input Modalities

    Make it easier for users to operate functionality through various inputs beyond keyboard.

    Success Criterion A AA AAA Message Name Applies To Techniques
    SC 2.5.1: Pointer Gestures (Level A)

    All 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.

    NoticeNoticeNotice

    Check that all 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.

    Top element.

    • N/A
    SC 2.5.2: Pointer Cancellation (Level A)

    For 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.

    NoticeNoticeNotice

    Check that for 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.

    Top element.

    • N/A
    NoticeNoticeNotice

    This element has a touchstart event listener. Check that for 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.

    Elements with touchstart event listener.

    • N/A
    NoticeNoticeNotice

    This element has a mousedown event listener. Check that for 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.

    Elements with mousedown event listener.

    • N/A
    SC 2.5.3: Label in Name (Level A)

    For user interface components with labels that include text or images of text, the name contains the text that is presented visually.

    NoticeNoticeNotice

    Check that for user interface components with labels that include text or images of text, the name contains the text that is presented visually.

    Top element.

    • N/A
    WarningWarningWarning

    Accessible name for this element does not contain the visible label text. Check that for user interface components with labels that include text or images of text, the name contains the text that is presented visually.

    Anchor (a), button, label, and input elements where the accessible name (via aria-labelledby, aria-label, or title attribute) does not contain the visible text.

    • F96
    SC 2.5.4: Motion Actuation (Level A)

    Functionality 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.

    NoticeNoticeNotice

    Check that functionality 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.

    Top element.

    • N/A
    WarningWarningWarning

    This element has a devicemotion event listener. Check that functionality 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.

    Elements with a devicemotion event listener.

    • N/A
    SC 2.5.5: Target Size (Level AAA)

    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.

    Notice

    Check that 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.

    Top element.

    • N/A
    SC 2.5.6: Concurrent Input Mechanisms (Level AAA)

    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.

    Notice

    Check that the 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.

    Top element.

    • N/A

    Principle 3: Understandable

    Guideline 3.1: Readable

    Make text content readable and understandable.

    Success Criterion A AA AAA Message Name Applies To Techniques
    SC 3.1.1: Language of Page (Level A)

    The default human language of each Web page can be programmatically determined.

    ErrorErrorError

    The html element should have a lang or xml:lang attribute which describes the language of the document.

    [Standard].Principle3.Guideline3_1.3_1_1.H57.2

    HTML element with no language attributes. The primary language of the page must be specified in the document, so it can be examined in an environment outside of a server.

    ErrorErrorError

    The language specified in the lang attribute of the document element does not appear to be well-formed.

    [Standard].Principle3.Guideline3_1.3_1_1.H57.3.Lang

    HTML element with a lang attribute (as used in HTML 4 and 5, including "polyglot" versions thereof) that is not well-formed.

    ErrorErrorError

    The language specified in the xml:lang attribute of the document element does not appear to be well-formed.

    [Standard].Principle3.Guideline3_1.3_1_1.H57.3.XmlLang

    HTML element with an xml:lang attribute (as used by XHTML) that is not well-formed.

    SC 3.1.2: Language of Parts (Level AA)

    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.

    NoticeNotice

    Ensure that any change in language is marked using the lang and/or xml:lang attribute on an element, as appropriate.

    [Standard].Principle3.Guideline3_1.3_1_2.H58

    Top element.

    ErrorError

    The language specified in the lang attribute of this element does not appear to be well-formed.

    [Standard].Principle3.Guideline3_1.3_1_2.H58.1.Lang

    Element (other than a HTML element) with a lang attribute (as used in HTML 4 and 5, including "polyglot" versions thereof) that is not well-formed.

    ErrorError

    The language specified in the xml:lang attribute of this element does not appear to be well-formed.

    [Standard].Principle3.Guideline3_1.3_1_2.H58.1.XmlLang

    Element (other than a HTML element) with an xml:lang attribute (as used by XHTML) that is not well-formed.

    SC 3.1.3: Unusual Words (Level AAA)

    A mechanism is available for identifying specific definitions of words or phrases used in an unusual or restricted way, including idioms and jargon.

    Notice

    Check that there is a mechanism available for identifying specific definitions of words or phrases used in an unusual or restricted way, including idioms and jargon.

    [Standard].Principle3.Guideline3_1.3_1_3.H40,H54,H60,G62,G70

    Top element.

    SC 3.1.4: Abbreviations (Level AAA)

    A mechanism for identifying the expanded form or meaning of abbreviations is available.

    Notice

    Check that a mechanism for identifying the expanded form or meaning of abbreviations is available.

    [Standard].Principle3.Guideline3_1.3_1_4.G102,G55,G62,H28,G97

    Top element.

    SC 3.1.5: Reading Level (Level AAA)

    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.

    Notice

    Where the content requires reading ability more advanced than the lower secondary education level, supplemental content or an alternative version should be provided.

    [Standard].Principle3.Guideline3_1.3_1_5.G86,G103,G79,G153,G160

    Top element.

    SC 3.1.6: Pronunciation (Level AAA)

    A mechanism is available for identifying specific pronunciation of words where meaning of the words, in context, is ambiguous without knowing the pronunciation.

    Error

    Ruby element does not contain an rt element containing pronunciation information for its body text.

    [Standard].Principle3.Guideline3_1.3_1_6.H62.1.HTML5

    Ruby element without a child rt element. This is the HTML5 version of ruby, where the base text is placed in the body of the ruby element.

    Error

    Ruby element does not contain an rt element containing pronunciation information for the text inside the rb element.

    [Standard].Principle3.Guideline3_1.3_1_6.H62.1.XHTML11

    Ruby element without a child rt element. This is the XHTML 1.1 version of ruby, where the base text is placed in a child rb element.

    Error

    Ruby element does not contain rp elements, which provide extra punctuation to browsers not supporting ruby text.

    [Standard].Principle3.Guideline3_1.3_1_6.H62.2

    Ruby element without child rp elements. These are necessary to provide punctuation for browsers that do not support ruby text.

    Guideline 3.2: Predictable

    Make Web pages appear and operate in predictable ways.

    Success Criterion A AA AAA Message Name Applies To Techniques
    SC 3.2.1: On Focus (Level A)

    When any component receives focus, it does not initiate a change of context.

    NoticeNoticeNotice

    Check that a change of context does not occur when any input field receives focus.

    [Standard].Principle3.Guideline3_2.3_2_1.G107

    Top element.

    SC 3.2.2: On Input (Level A)

    Changing the setting of any user interface component does not automatically cause a change of context unless the user has been advised of the behavior before using the component.

    ErrorErrorError

    Form does not contain a submit button (input type="submit", input type="image", or button type="submit").

    [Standard].Principle3.Guideline3_2.3_2_2.H32.2

    Forms which do not provide an ability on their interface to be submitted using the mouse.

    SC 3.2.3: Consistent Navigation (Level AA)

    Navigational 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.

    NoticeNotice

    Check that navigational mechanisms that are repeated on multiple Web pages occur in the same relative order each time they are repeated, unless a change is initiated by the user.

    [Standard].Principle3.Guideline3_2.3_2_3.G61

    Top element.

    SC 3.2.4: Consistent Identification (Level AA)

    Components that have the same functionality within a set of Web pages are identified consistently.

    NoticeNotice

    Check that components that have the same functionality within this Web page are identified consistently in the set of Web pages to which it belongs.

    [Standard].Principle3.Guideline3_2.3_2_4.G197

    Top element.

    SC 3.2.5: Change on Request (Level AAA)

    Changes of context are initiated only by user request or a mechanism is available to turn off such changes.

    Warning

    Check that this link's link text contains information indicating that the link will open in a new window.

    [Standard].Principle3.Guideline3_2.3_2_5.H83.3

    Link elements that have a "_blank" target attribute, meaning it will open in a new window, but do not have text saying that (the words "new window" are looked for, specifically, case insensitive).

    Guideline 3.3: Input Assistance

    Help users avoid and correct mistakes.

    Success Criterion A AA AAA Message Name Applies To Techniques
    SC 3.3.1: Error Identification (Level A)

    If an input error is automatically detected, the item that is in error is identified and the error is described to the user in text.

    NoticeNoticeNotice

    If an input error is automatically detected in this form, check that the item(s) in error are identified and the error(s) are described to the user in text.

    [Standard].Principle3.Guideline3_3.3_3_1.G83,G84,G85

    Form elements in general.

    SC 3.3.2: Labels or Instructions (Level A)

    Labels or instructions are provided when content requires user input.

    NoticeNoticeNotice

    Check that descriptive labels or instructions (including for required fields) are provided for user input in this form.

    [Standard].Principle3.Guideline3_3.3_3_2.G131,G89,G184,H90

    Form elements in general.

    SC 3.3.3: Error Suggestion (Level AA)

    If an input error is automatically detected and suggestions for correction are known, then the suggestions are provided to the user, unless it would jeopardize the security or purpose of the content.

    NoticeNotice

    Check that this form provides suggested corrections to errors in user input, unless it would jeopardize the security or purpose of the content.

    [Standard].Principle3.Guideline3_3.3_3_3.G177

    Form elements in general.

    SC 3.3.4: Error Prevention (Legal, Financial, Data) (Level AA)

    For Web pages that cause legal commitments or financial transactions for the user to occur, that modify or delete user-controllable data in data storage systems, or that submit user test responses, 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.

    Editor's Note: Superseded by Success Criterion 3.3.6 at level AAA, which extends this requirement to all forms.

    Notice

    If this form would bind a user to a financial or legal commitment, modify/delete user-controllable data, or submit test responses, ensure that submissions are either reversible, checked for input errors, and/or confirmed by the user.

    [Standard].Principle3.Guideline3_3.3_3_4.G98,G99,G155,G164,G168.LegalForms

    Form elements in general.

    SC 3.3.5: Help (Level AAA)

    Context-sensitive help is available.

    Notice

    Check that context-sensitive help is available for this form, at a Web-page and/or control level.

    [Standard].Principle3.Guideline3_3.3_3_5.G71,G184,G193

    Form elements in general.

    SC 3.3.6: Error Prevention (All) (Level AAA)

    For 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.
    Notice

    Check that submissions to this form are either reversible, checked for input errors, and/or confirmed by the user.

    [Standard].Principle3.Guideline3_3.3_3_6.G98,G99,G155,G164,G168.AllForms

    Form elements in general.

    Principle 4: Robust

    Guideline 4.1: Compatible

    Maximize compatibility with current and future user agents, including assistive technologies.

    Success Criterion A AA AAA Message Name Applies To Techniques
    SC 4.1.1: Parsing (Level A)

    In content implemented using markup languages, elements have complete start and end tags, elements are nested according to their specifications, elements do not contain duplicate attributes, and any IDs are unique, except where the specifications allow these features.

    Note: Start and end tags that are missing a critical character in their formation, such as a closing angle bracket or a mismatched attribute value quotation mark are not complete.

    ErrorErrorError

    Duplicate id attribute value "[Element ID]" found on the web page.

    [Standard].Principle4.Guideline4_1.4_1_1.F77

    Second and subsequent sightings of an element ID.

    SC 4.1.2: Name, Role, Value (Level A)

    For all user interface components (including but not limited to: form elements, links and components generated by scripts), the name and role can be programmatically determined; states, properties, and values that can be set by the user can be programmatically set; and notification of changes to these items is available to user agents, including assistive technologies.

    Note: This success criterion is primarily for Web authors who develop or script their own user interface components. For example, standard HTML controls already meet this success criterion when used according to specification.

    WarningWarningWarning

    Anchor element found with an ID but without a href or link text. Consider moving its ID to a parent or nearby element.

    [Standard].Principle4.Guideline4_1.4_1_2.H91.A.Empty

    Empty anchor element (no text, no href) but with an ID. In HTML5, this breaks the intended role of an "A" element being a link. (In HTML 4.01, this is legal.) The ID should be placed on something more concrete, unless the ID is used for reasons like scripting.

    WarningWarningWarning

    Anchor element found with a name attribute but without a href or link text. Consider moving the name attribute to become an ID of a parent or nearby element.

    [Standard].Principle4.Guideline4_1.4_1_2.H91.A.EmptyWithName

    Empty anchor element (no text, no href) but with a name attribute. In HTML5, this breaks the intended role of an "A" element being a link, and the name attribute is also obsolete. (In HTML 4.01, this is legal.) This is the older method of creating an in-page link target, using the name attribute instead of ID.

    ErrorErrorError

    Anchor element found with no link content and no name and/or ID attribute.

    [Standard].Principle4.Guideline4_1.4_1_2.H91.A.EmptyNoId

    Completely empty anchor element (no text, no href, no ID).

    WarningWarningWarning

    Anchor elements should not be used for defining in-page link targets. If not using the ID for other purposes (such as CSS or scripting), consider moving it to a parent element.

    [Standard].Principle4.Guideline4_1.4_1_2.H91.A.NoHref

    Anchor element with no href, but with an ID and text. This breaks the intended role of an "A" element being a link. It will usually be around text inside another parent element (such as a heading); the ID should be moved up for the same effect.

    WarningWarningWarning

    Anchor element found with link content, but no href and/or ID attribute has been supplied.

    [Standard].Principle4.Guideline4_1.4_1_2.H91.A.Placeholder

    Link with text, but no href or ID. This means it does not have an accessibility API "value". It only counts as a warning, because in the latest HTML5 draft, an "A" element can be specified without a href.

    ErrorErrorError

    Anchor element found with a valid href attribute, but no link content has been supplied.

    [Standard].Principle4.Guideline4_1.4_1_2.H91.A.NoContent

    Link with a href attribute, but without link text. This means it does not have an accessibility API "name".

    ErrorErrorError

    This [element type] does not have a name available to an accessibility API. Valid names are [valid names for this element].

    [Standard].Principle4.Guideline4_1.4_1_2.H91.[NodeName].Name

    Form control which does not have a valid accessibility API "name". The message states which items count as a valid "name".

    ErrorErrorError

    This [element type] does not have a value available to an accessibility API. Add one [using a element-specific method].

    [Standard].Principle4.Guideline4_1.4_1_2.H91.[NodeName].Value

    Form control which does not have a valid accessibility API "value". The message states how to add a valid value.

    SC 4.1.3: Status Messages (Level AA)

    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.

    NoticeNotice

    Check that 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.

    Top element.

    • ARIA22
    • G199
    • ARIA19
    • G83
    • G84
    • G85
    • G139
    • G177
    • G194
    • ARIA23
    • ARIA22