Rule ID: ace-media-video-caption

Check that video elements include synchronized captions for deaf and hard-of-hearing users

WCAG 2.0 (A) - WCAG 2.2 (A) 1.2.2: Captions (Prerecorded) Deaf Legal Risk

What This Rule Checks

Captions make video content accessible to users who are deaf or hard of hearing by providing a text-based representation of dialogue and important sound effects. Good captions include dialogue, speaker identification, and non-speech audio information like meaningful sound effects

Who Is Affected

This issue primarily affects: Deaf users, who cannot hear audio content and rely on captions or transcripts.

Why This Matters

Videos without captions are completely inaccessible to deaf and hard-of-hearing users. Captions also benefit users in noisy environments or who process written text better than speech. This is a WCAG 1.2.2 Level A violation.

How to Fix

Ensure all videos have captions using the <track> element in HTML or by embedding captions directly into the video file.

Code Examples

Incorrect Markup Solutions:
Code example
<!-- Video with no captions --> <video src="product-demo.mp4" controls></video> Copy
Correct Markup Solutions:
Code example
<!-- Video with captions track --> <video src="product-demo.mp4" controls> <track kind="captions" src="demo-en.vtt" srclang="en" label="English captions" default> </video> Copy

Common Mistakes to Avoid

  • Confusing subtitles with captions (captions also include sound effects and speaker identification).
  • Using auto-generated captions without reviewing for accuracy.
  • Not providing captions for user-generated video content.
  • Embedding videos from third-party platforms without ensuring caption availability.

Tip: Multimedia content must be accessible to users who cannot see or hear. Provide captions for video, transcripts for audio, and text descriptions for visual-only content. Always include user-controllable playback.

Related WCAG Criteria

  • 1.2.2: Captions (Prerecorded)