Web Accessibility WCAG 2.1 Knowledge Base

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Conformance Levels

Web Accessibility and WCAG 2.1 is a relatively new area of expertise for many web developers and webmasters. We’re working to build a comprehensive knowledge base of questions and answers to help solve the unique challenges around building websites with web accessibility in mind.  Browse or search our knowledge base, or submit questions to our team of developers. If you need more help, learn more about our WCAG audits and accessibility scanning platform.

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Browse Recent Questions & Answers

Why does an auto-playing video require a pause mechanism?

We often use background videos (looped, no sound) in the hero with i.e. the headline on it. It's a great eyecatcher and the users like it a lot. The WCAG guideline says that this should not be allowed if the video does not stop after...

  • autoplay
  • video

In web accessibility, which text is part of the visible label?

I’ve built form fields that are part of a sentence — I basically want the user to fill in the blanks. However, that also means there is a lot of text near the form fields. Which text counts as the visible label?

  • form fields
  • forms
  • visible labels

What are the hover state contrast requirements for drop down lists?

I have a dropdown list with black text in a form. Does the background bar on the hover states as you hover over each selection option require a 3.1 contrast ratio against the white container background, or can I use a light gray background bar...

  • color contrast
  • drop down
  • focus state
  • hover state