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Audio & video

Sound Plays by Itself and Can't Be Stopped Quickly

Audio that starts on its own talks over the screen reader, so people who rely on speech can't hear the page or find the stop button.

no-autoplay-audioWCAG 2.0Introduced in WCAG 2.0.Level AA — the minimum. Missing it blocks people outright.

Status
CriticalCritical — Someone can complete the task only with great difficulty or outside help.CurrentScanners run this rule today.
Owner
All roles
Audit
Automated+ManualA scanner finds it; a person confirms the fix.

Why it matters

Screen readers speak the page aloud. When a video or song starts by itself, the two voices clash. The person may not be able to hear enough to find the pause button.

Sudden sound also startles people, breaks concentration and can embarrass someone in a quiet office. Sound that stops within three seconds, or comes with an easy stop or mute control, is fine.

Who it affects

Who it affects, and how much
WhoWhat they experienceImpact
Screen reader usersThey hear the audio drowning out their screen reader, and may give up before finding the stop button.High impact
Cognitive and neurodivergent usersSudden sound distracts them and makes it hard to read or think.High impact
Low-vision users (magnification)Those using a screen reader face the same clash. Those using zoom may struggle to find a small mute button.Partial impact
Keyboard-only usersIf the mute control is hard to reach by keyboard, they must Tab through the page while it plays.Partial impact
Voice control usersThe audio can confuse their speech software and block their commands.Partial impact
Motor and dexterityLittle effect, unless the stop control is small and hard to hit.Partial impact

Business & product impact

Business & product impact, with how much each claim weighs
AreaWhyImpact
LegalIt fails WCAG 1.4.2 at Level A, the minimum. Complaints under Australia's Disability Discrimination Act point to WCAG, and EN 301 549 includes the same rule.High impact
ConversionMany people close a tab the moment sound blasts out. Some never come back.High impact
SEONo real search benefit — don't sell it as one.Low impact
Brand trustAutoplaying sound is widely disliked. It makes a site feel pushy.Moderate impact
Cost to fixUsually a small change: remove `autoplay` or add `muted`. The harder part is agreeing it with the team.High impact

Fixing it in code

A hero video with sound

Don't

<video src="promo.mp4" autoplay></video>

A screen reader says: “The video's soundtrack starts and talks over the screen reader.”

Do

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

A screen reader says: “Video, play button. Nothing plays until the person chooses.”

The person decides when sound starts, and the controls let them stop it.

A background video that must autoplay

Don't

<video src="loop.mp4" autoplay loop></video>

A screen reader says: “Looping sound plays over everything, with no way to stop it.”

Do

<video src="loop.mp4" autoplay loop muted playsinline></video>

A screen reader says: “Silent. The screen reader can be heard clearly.”

Muted video makes no sound, so nothing clashes with speech.

Designer's handoff note

Design media to start paused or muted. If sound is part of the idea, show a clear play button.

Put any pause or mute control near the top, easy to see and reach first by keyboard.

Quick test

Tool

NVDA (opens in a new tab) (free for Windows) or VoiceOver (opens in a new tab) (on every Mac)

Checklist

Pass
No sound plays, or it stops within three seconds.
Fail
Sound keeps playing and you have to hunt for a way to stop it.

What a green scan still misses

A scanner sees the autoplay attribute but can't tell if the clip is short, silent or easy to stop. It also misses sound started by JavaScript or inside embedded players.

Reference

Rule ID
no-autoplay-audio
Raised by
  • axe-core: “<video> or <audio> elements must not play automatically”
WCAG
Other standards
EN 301 549 9.1.4.2 · RGAA 4.10.1
Last reviewed
14 October 2026