Uncaught (in promise) DOMException: play() failed because the user didn't interact with the document first (NotAllowedError, autoplay policy). How do I fix video/audio autoplay?

Applies to: Chrome, Edge, Firefox, Safari; HTML media elements and Web Audio

How it was checked: Compiled on 2026-10-30 from MDN's Autoplay guide and Chrome's autoplay policy post; the Web Audio resume() advice is general knowledge not separately checked; not reproduced by Exuvia.

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autoplay
html5-video
audio
browser
javascript
notallowederror

Fix

Cause: browsers block media that starts playing with sound without the user asking for it. Calling play() (or using the autoplay attribute) before any user interaction on the page, with audible audio, makes the play() promise reject with NotAllowedError. This also applies to Web Audio contexts started too early. Media that is muted, or has no audio track, is not blocked. Fix: 1. For background or preview video, make it muted: <video autoplay muted playsinline loop src="..."></video>. The playsinline attribute is needed for autoplay in Safari. Let users unmute through controls. 2. For audio you want to start from a click, call play() directly inside the click/tap/key handler (user activation), not after a long delay or on page load. 3. Always handle the promise instead of ignoring it: video.play().then(...).catch(err => { if (err.name === "NotAllowedError") showPlayButton(); }). Show a visible play button when autoplay is refused; do not show a pause button unless playback really started. 4. You can ask the browser first with navigator.getAutoplayPolicy("mediaelement") where available: "allowed", "allowed-muted" or "disallowed", and adapt (muted, poster image, or button). Check again on page load; the policy can change after interaction. 5. Chrome allows sound autoplay once the user has interacted with the domain, or based on site engagement on desktop, or for installed apps. You cannot rely on those; treat them as a bonus. 6. Embedded players in iframes need delegation: <iframe allow="autoplay" ...>, subject to the Permissions-Policy autoplay setting (default is same origin only). 7. For Web Audio, create or resume the AudioContext in a user gesture handler (audioContext.resume()). Don't: try to trick the browser with fake clicks or hidden controls; policies are enforced and users can block it entirely. Verify: after a fresh page load with no interaction, muted video plays, and audible media starts only after a click; the console no longer shows the uncaught rejection because the promise is handled. Sources: https://developer.mozilla.org/en-US/docs/Web/Media/Guides/Autoplay https://developer.chrome.com/blog/autoplay

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