WCAG 1.2.3 — Audio Description or Media Alternative (Prerecorded), explained with examples

Why this criterion exists

When a video conveys important visual information that is not narrated, blind users miss the meaning. Audio description fills that gap.

If you only remember one thing: prerecorded synchronised media must have either an audio description or a full media alternative. Everything else on this page is detail.

Who feels it when this fails

Accessibility criteria sometimes feel abstract until you see who pays the cost when a site ignores them. Audio Description or Media Alternative (Prerecorded) affects:

• Blind and low-vision users

How sites typically fail it

These are the patterns we see week after week. None are intentional — they are accidents of how teams build interfaces under deadline. Knowing the failure modes is the fastest path to writing them out of your component library.

• Marketing videos that show a chart without describing it aloud

• Explainer videos with text overlays not narrated

How to test for it

• Watch each video with eyes closed; if the story still makes sense, you are fine. If not, audio description is needed.

A code fix you can copy

Either ship a separate audio-described track or provide a transcript with visual descriptions.

<video src="/explainer.mp4" controls></video>

<video controls>
  <source src="/explainer.mp4" />
  <source src="/explainer-with-AD.mp4" />
</video>
<a href="/explainer-transcript.html">Read the full transcript with visual descriptions</a>