WCAG Guideline 1.2.7: Extended Audio Description (Prerecorded) Explained
Estimated read time: 8–10 minutes
Guideline 1: Perceivable
The first principle of WCAG, Perceivable, ensures that information and user interface components must be presented to users in ways they can perceive. This means content can’t be invisible to all of a user’s senses—whether they are seeing, hearing, or feeling the content through assistive technology.
Guideline 1.2: Time-based Media
Guideline 1.2 focuses on making time-based media—like audio and video—accessible to everyone. This includes providing alternatives such as transcripts, captions, and audio descriptions so users with different abilities can access the content.
What Is Guideline 1.2.7 Extended Audio Description (Prerecorded)?
"Where pauses in foreground audio are insufficient to allow audio descriptions to convey the sense of the video, extended audio description is provided for all prerecorded video content in synchronized media."
Guideline 1.2.7 is a Level AAA requirement in the Web Content Accessibility Guidelines (WCAG) .
- All prerecorded video content with audio should have extended audio description if standard audio description is not sufficient.
- Extended audio description provides additional narration during pauses to describe important visual details.
- This is especially important for complex or fast-paced videos where standard audio description can't keep up.
This ensures that users who are blind or have low vision can fully understand your video content.
Why Does It Matter?
- Inclusivity: Extended audio description provides access for users who are blind or have low vision.
- Legal Compliance: This is a Level AAA requirement in WCAG 2.2.
- Usability: Enhances understanding for users who rely on audio cues to follow video content.
For more, see W3C's audio description docs .
What Needs Extended Audio Description?
- Prerecorded video content with audio (movies, tutorials, online courses)
- Any synchronized media where standard audio description is insufficient
All such media should have extended audio description available.
How to Provide Extended Audio Description
- Add additional narration during pauses in the video
- Use professional audio description services or tools
- Make the audio description option easy to enable and hear
- Ensure descriptions are accurate and synchronized
For more, see W3C's audio description docs .
Common Mistakes to Avoid
- No extended audio description for complex video content
- Audio description that is out of sync or hard to hear
- Not making the audio description option easy to find
- Using unqualified narrators
Audit your site regularly and use accessibility checkers to ensure all video content has proper extended audio description. For more, see the Netflix Audio Description Style Guide v2.5 .
Differences Between A, AA, and AAA for Guideline 1.2.7 in WCAG 2.2
- Level A: No requirement for 1.2.7.
- Level AA: No requirement for 1.2.7.
- Level AAA: Requires extended audio description for all prerecorded video content in synchronized media where standard audio description is insufficient. This is the core requirement for 1.2.7 and is mandatory for AAA conformance.
For more, see the W3C’s official documentation for 1.2.7 Extended Audio Description (Prerecorded) .
Quick Checklist
- All prerecorded video content with audio has extended audio description if needed
- Audio description is accurate and synchronized
- Audio description option is easy to enable and hear
- Narrators are qualified and clear
- Tested with users and assistive technology
Summary
Guideline 1.2.7 is essential for making video content accessible to users who rely on audio description. By providing extended audio description, you support users with disabilities, improve usability, and meet AAA requirements. Make audio description a standard part of your video production process for maximum inclusion.