Chrome's new Media Engagement Index

Chrome 66, released on tax day (yesterday), introduces some new heuristics regarding media playback, specifically when ‘autoplay’ will be respected. Pretty smart stuff! It takes into account your behavior:

Media Engagement Index (MEI)

The MEI measures an individual’s propensity to consume media on a site. Chrome’s current approach is a ratio of visits to significant media playback events per origin:

  • Consumption of the media (audio/video) must be greater than 7 seconds.
  • Audio must be present and unmuted.
  • Tab with video is active.
  • Size of the video (in px) must be greater than 200x140.

From that, Chrome calculates a media engagement score which is highest on sites where media is played on a regular basis. When it is high enough, media playback is allowed to autoplay on desktop only.


You can see this by visiting: chrome://media-engagement/, which looks like this for me and lists significant playbacks – domains which I trust to blast audio:

The article also recommends a promise to determine if Autoplay (with audio) was accepted. And if not, then show a play button. So if something depends on video or audio playback, make sure you check that it is actually playing first.

If you’re currently hitting issues in Chrome with audio, please see this thread.

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Here is a way that may help unlock audio for now…

Chrome made some updates to this policy:

https://developers.google.com/web/updates/2018/11/web-audio-autoplay

If you have audio that should autoplay, the same rules apply: start your audio after some interaction with the page. If enough people are allowing audio on your site, your site may be added to an algorithmically-generated pre-seed list: https://sites.google.com/a/chromium.org/dev/audio-video/autoplay/autoplay-pre-seeding-in-chrome, where audio will be allowed to autoplay. Since this system is very new, it is likely to change a bit in the future.