MediaEncryptedEvent: initData property

Baseline Widely available

This feature is well established and works across many devices and browser versions. It’s been available across browsers since March 2019.

The read-only initData property of the MediaKeyMessageEvent returns the initialization data contained in this event, if any.

Value

An ArrayBuffer with the initialization data, or null if there are none.

Specification
Encrypted Media Extensions # dom-mediaencryptedevent-initdata

	desktop					mobile
	Chrome	Edge	Firefox	Opera	Safari	Chrome Android	Firefox for Android	Opera Android	Safari on iOS	Samsung Internet	WebView Android	WebView on iOS
`initData`	Chrome – Full support Chrome 42 (Release date: 2015-04-14) footnote Full support	Edge – Full support Edge 13 (Release date: 2015-11-12) footnote Full support	Firefox – Full support Firefox 38 (Release date: 2015-05-12) footnote Full support	Opera – Full support Opera 29 (Release date: 2015-04-28) footnote Full support	Safari – Full support Safari 12.1 (Release date: 2019-03-25) footnote Full support	Chrome Android – Full support Chrome Android 42 (Release date: 2015-04-15) footnote Full support	Firefox for Android – Full support Firefox for Android 38 (Release date: 2015-05-12) footnote Full support	Opera Android – Full support Opera Android 29 (Release date: 2015-04-28) footnote Full support	Safari on iOS – Full support Safari on iOS 12.2 (Release date: 2019-03-25) footnote Full support	Samsung Internet – Full support Samsung Internet 4 (Release date: 2016-03-11) footnote Full support	WebView Android – Full support WebView Android 43 (Release date: 2015-05-27) footnote Full support	WebView on iOS – Full support WebView on iOS 12.2 (Release date: 2019-03-25) footnote Full support

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This page was last modified on Oct 30, 2025 by MDN contributors.

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