WCAG 2.1 A Standards

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Conformance Levels

Your baseline for web accessibility

Single-A is your baseline for website conformance. With this level a website can be considered to have gone through basic website review, repair, and content considered and consider to have a basic level of accessibility. Criteria to meet Single-A conformance cover needs and considerations related to: mixed media, HTML markup, graphic design, forms, navigation, and usability considerations.

Single-A Overview


  • All images have a descriptive, unique ALT tag.
  • Audio/video-only media has an alternate means to deliver content: a collapsible text-version, alternative caption/audio track, or a downloadable companion.
  • Captions, a transcription, or descriptions are included within streaming media.
  • Streaming audio does not start automatically without pause/play controls.
  • Controls for auto-playing media have pause, stop, and hide controls.


  • If present, the website uses Aria roles and HTML5 tags appropriately.
  • Webpage makes sense if you view it after having turned off JS/CSS.
  • A TITLE element is included to differentiate pages.
  • The human language of the content on the page is declared.
  • The page does not include any parsing errors and has “clean” code without extra, excess, or erroneous tags.


  • User Interface or content elements are differentiated through more than just color, such that colorblind individuals can differentiate and gain the intended meaning.
  • When using TAB keys to navigate to form elements or links, there is a CSS Focus state (usually a semi-transparent outline) that shows what element the user is on.
  • Content does not include a “flash” or “strobe” effect that covers the screen and lasts longer than 3 seconds.
  • Text used in a hyperlink clearly describes what users might expect to find after clicking, unless the content found is intended to be obfuscated.
  • When being targeted/navigated to by Focus, elements don’t change in function – they should act the same way as when using a mouse.


  • Unless declared beforehand, entering content into a form doesn’t change that element.
  • If an error is detected in a form it is identified & described – usually with an asterisk.
  • Forms and UI elements can be programmatically determined and used without a keyboard and mouse. This typically means that elements include: name, roles, and value.
  • User can navigate between form elements using the tab or arrow keys.


  • You can navigate and perform necessary actions on the website using just a keyboard.
  • Add a “skip to content” button that can jump users past navigation to the main content.
  • When tab or arrow navigating, focus states are displayed in a logical order.


  • Reasonable accommodations for extending or bypassing time limits (such as “check out within 5 minutes” or “you will be logged out in 45 seconds”) are made, such as allowing the user to extend the time limit.

Success Criterion