1.4.7 Low or No Background Audio
Level AAA · added in WCAG 2.0
In prerecorded audio that is mostly speech, background sound must be absent or able to be turned off. Otherwise, it must be at least 20 dB quieter than the speech. This is level AAA, which most laws and policies don't require, but it makes podcasts and narration much easier to follow.
Who it helps
People who are hard of hearing, including many older adults and hearing aid users, struggle to separate speech from music or noise. People with auditory processing or attention difficulties benefit too.
How to meet it
- Record speech in a quiet space so the voice track starts clean.
- Mix music and effects at least 20 dB below the speech, which is about four times quieter.
- Or offer a version without background sound, or a control that turns it off.
- Occasional sounds that last only one or two seconds, like a door closing, may be louder.
- Know the scope: it covers prerecorded audio-only speech; audio CAPTCHAs, audio logos, and singing or rapping are exempt.
- Check levels with your audio editor's meters instead of judging by ear.
Examples
<h2>Episode 8: Planning your first trip</h2>
<audio controls src="/audio/ep8-with-music.mp3"></audio><h2>Episode 8: Planning your first trip</h2>
<audio controls src="/audio/ep8-with-music.mp3"></audio>
<p><a href="/audio/ep8-speech-only.mp3">
Listen without background music</a></p>Can a scanner detect this?
No
No axe-core rule tests this criterion, because web scanners don't analyze the sound inside audio files. Measure the speech and background levels in an audio editor, or listen closely to the final mix.
No automated rule tests this criterion. Check it by hand.
Common mistakes
- Running music under narration at nearly the same loudness as the voice.
- Keeping ambient sound under a whole episode with no version that removes it.
- Checking the mix only on studio headphones, where speech is easier to pick out.
Related criteria
Check your own page
See which automated WCAG checks your page fails, with the failing elements and how to fix them.
Reviewed November 2, 2026