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Website accessibility is about designing and developing your website to make it usable and accessible for users with disabilities. More specifically, accessibility allows disabled users to perceive, understand, navigate, and interact with your website.

Improving your site's accessibility also has a number of user benefits for those who are not disabled, such as users on smaller screens, older users, and people with 'situational limitations' such as in bright sunlight or in an environment where they cannot listen to audio

Automated accessibility testing

Sitebulb's accessibility audit utilizes the open source axe library developed by Deque, running 50+ automated accessibility checks against the content and code of every page of your website.

This is the same technology that powers the accessibility audit in Google's Lighthouse tool, so you can perform a spot-check on a single URL or debug further in the browser using Lighthouse.

Sitebulb's Hint system will show you every violation found on each page, and each violation is wired up to the Deque University axe Rules via a Learn More link, which explain what the rule means, what it is looking for, and how to fix it.

Accessibility Hints

Accessibility Hints

The accessibility ruleset spans a number of different aspects, as follows:

WCAG 2.0 Level A & AA Rules

  1. <audio> elements must have a captions <track>
  2. <blink> elements are deprecated and must not be used
  3. <dl> elements must only directly contain properly-ordered <dt> and <dd> groups, <script>, or <template> elements
  4. <dt> and <dd> elements must be contained by a <dl>
  5. <html> element must have a lang attribute
  6. <html> element must have a valid value for the lang attribute
  7. <html> elements with lang and xml:lang must have the same base language
  8. <li> elements must be contained in a <ul> or <ol>
  9. <marquee> elements are deprecated and must not be used
  10. <object> elements must have alternate text
  11. <ul> and <ol> must only directly contain <li>, <script> or <template> elements
  12. <video> elements must have a <track> for captions
  13. Active <area> elements must have alternate text
  14. All <th> elements and elements with role="columnheader" or role="rowheader" must have data cells they describe
  15. All cells in a <table> element that use the headers attribute must only refer to other cells of that same <table>
  16. ARIA attributes must conform to valid names
  17. ARIA attributes must conform to valid values
  18. ARIA button, link, and menuitem must have an accessible name
  19. ARIA input fields must have an accessible name
  20. ARIA meter must have an accessible name
  21. ARIA progressbar must have an accessible name
  22. ARIA roles used must conform to valid values
  23. ARIA toggle fields have an accessible name
  24. ARIA tooltip must have an accessible name
  25. aria-hidden elements do not contain focusable elements
  26. aria-hidden="true" must not be present on the document <body>
  27. Audio must have controls that provide users with the ability to stop automatically played audio after three seconds
  28. Buttons must have discernible text
  29. Certain ARIA roles must be contained by particular parent elements
  30. Certain ARIA roles must contain particular children
  31. Documents must contain a title element to aid in navigation
  32. Elements containing role="img" have an alternative text
  33. Elements must only use allowed ARIA attributes
  34. Ensure that scrollable region has keyboard access
  35. Ensures <frame> and <iframe> elements with focusable content do not have tabindex=-1
  36. Form <input> elements must have labels
  37. Form fields do not have duplicate labels
  38. Frames must have title attribute
  39. ID attribute value must be unique
  40. ID attribute values must be unique
  41. IDs used in ARIA and labels must be unique
  42. Image buttons must have alternate text
  43. Images must have alternate text
  44. Input buttons must have discernible text
  45. lang attribute must have a valid value
  46. Links must have discernible text
  47. Nested interactive controls are not announced by screen readers
  48. Page must have means to bypass repeated blocks
  49. Required ARIA attributes must be provided
  50. select element must have an accessible name
  51. Server-side image maps must not be used
  52. SVG images and graphics require accessible text
  53. Text elements must have sufficient color contrast against the background
  54. Timed refresh must not exist
  55. Use aria-roledescription on elements with a semantic role

WCAG 2.1 Level A & AA Rules

  1. Autocomplete attribute must be used correctly
  2. Inline text spacing must be adjustable with custom stylesheets

WCAG 2.0 and 2.1 level AAA rules

  1. All text elements must have sufficient contrast between text in the foreground and background colors behind it in accordance with WCAG 2 AAA contrast ratio thresholds.
  2. Ensure that links with the same accessible name serve a similar purpose
  3. Meta refresh must not exist

Best Practice Rules

  1. accesskey attribute value must be unique
  2. All page content must be contained by landmarks
  3. ARIA dialog and alertdialog must have an accessible name
  4. ARIA role must be appropriate for the element
  5. ARIA treeitem must have an accessible name
  6. Banner landmark must not be contained in another landmark
  7. Complementary landmarks and/or asides are top level
  8. Contentinfo landmark must not be contained in another landmark
  9. Elements should not have tabindex greater than zero
  10. Elements whose role is none or presentation must not conflict with other roles
  11. Ensures role="text" is used on elements with no focusable descendants
  12. Ensures table headers have discernible text
  13. Ensures the document has at most one main landmark
  14. Form <input> elements should have a visible label
  15. Frames must be tested with axe-core
  16. Frames must have a unique title attribute
  17. Heading levels should only increase by one
  18. Headings must not be empty
  19. Landmarks must have a unique role or role/label/title (i.e. accessible name) combination
  20. Main landmark must not be contained in another landmark
  21. Page must contain a level-one heading
  22. Page must have one main landmark
  23. Page must not have more than one banner landmark
  24. Page must not have more than one contentinfo landmark
  25. Scope attribute should be used correctly on tables
  26. Text of buttons and links should not be repeated in the image alternative
  27. The <caption> element should not contain the same text as the summary attribute
  28. The skip-link target should exist and be focusable
  29. Users should be able to zoom and scale the text up to 500%
  30. Zooming and scaling must not be disabled

Experimental Rules

  1. All non-empty <td> elements in tables larger than 3 by 3 must have an associated table header
  2. Bold, italic text and font-size are not used to style <p> elements as a heading
  3. CSS Media queries are not used to lock display orientation
  4. Data or header cells should not be used to give caption to a data table
  5. Elements in the focus order need a role appropriate for interactive content
  6. Hidden content on the page cannot be analyzed
  7. Label and name from content mismatch
  8. Links must be distinguished from surrounding text in a way that does not rely on color


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