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WCAG 2.1 Criteria Documentation

1.2.5: Audio Description (Prerecorded) – Level AA

High-Level Description

This criterion requires that pre-recorded video content with audio includes an audio description — a spoken narration that describes important visual content not conveyed in the audio alone.
It ensures that blind or visually impaired users can access the full meaning of video by hearing what's happening visually — such as actions, scenes, facial expressions, or on-screen text.

Detailed Description

When it Applies:

  • The content is a pre-recorded video with synchronised audio.
  • Key visual elements convey meaning not already included in the audio.
  • The visuals are essential to understanding the video - character gestures, environment, text on screen.

What’s Required:

  • An audio description track that describes important visual details during natural pauses in dialogue.
  • The description can be:
    • Built into the main audio track.
    • Provided as a separate audio track, through media players that support it.

Indicators of Non-Compliance:

  • Important visual content is not described in the audio or captions.
  • Audio description is missing for complex visual scenes e.g. action without dialogue.
  • Separate description track is provided, but not announced or discoverable.
  • On-screen text is never read aloud or described.
  • Videos that include storytelling or emotion through visuals are inaccessible without narration e.g. facial expressions.

Real-World Examples & Scenarios

ScenarioCompliantNon-Compliant
Drama Series Clip An audio description says: "She reads the letter and gasps, dropping it as her eyes fill with tears."A character silently opens a letter and reacts with shock. Regular audio doesn't explain this.
Software Tutorial VideoAn audio description would fill the gaps: "The user clicks the 'Export' button in the top-right corner."A pointer moves across the screen selecting buttons, but the narrator doesn't say what's being clicked.
Event Recap VideoThe audio description adds "Scoreboard shows 2-1 victory for Dublin. Fans wave flags in the stands."A sports highlight reel shows crowd reactions, player celebrations, and scores on screen - all without voiceover.

Disability Impact

Disability GroupWithout Audio DescriptionWith Audio Description
BlindCannot understand visual events or scene changesGains full access to story, context, and content
Low VisionMay miss text or subtle visual cuesAudio fills in missing information

Supporting Documentation & Legal References

Remediation Strategies with Tools and Code

    Narrate all visual actions in the video as part of the main script. Best for:

  • Tutorials
  • Product walkthroughs
  • Training videos
  • Example - "Now click the green 'Submit' button on the bottom left corner."

    If you're working with media platforms like Youtube, Vimeo, or HTML5 video:

  • Record a separate narration track describing the visuals.
  • Allow the user to select it via captions or settings.

    If audio description is not technically feasible, provide a full transcript of both spoken dialogue and visual description.
    Example - [Narrator]: "Today we're reviewing the new app layout."
    [Visual]: The app's home screen shows three buttons labelled 'Home,' 'Profile,' and 'Settings'.