MediaRecorder: requestData() method

Baseline Widely available

This feature is well established and works across many devices and browser versions. It’s been available across browsers since April 2021.

See full compatibility

The requestData() method of the MediaRecorder interface is used to raise a dataavailable event containing a Blob object of the captured media as it was when the method was called. This can then be grabbed and manipulated as you wish.

When the requestData() method is invoked, the browser queues a task that runs the following steps:

If MediaRecorder.state is "inactive", raise a DOM InvalidState error and terminate these steps. If MediaRecorder.state is not "inactive", continue to the next step.
Raise a dataavailable event containing a Blob of the currently captured data (the Blob is available under the event's data attribute.)
Create a new Blob and place subsequently captured data into it.

Syntax

requestData()

Parameters

None.

Return value

None (undefined).

Exceptions

InvalidStateError DOMException: Thrown if the MediaRecorder is currently "inactive"; you cannot capture the recording if the MediaRecorder is not active.

Examples

captureMedia.onclick = () => {
  mediaRecorder.requestData();
  // makes snapshot available of data so far
  // ondataavailable fires, then capturing continues
  // in new Blob
};

Specifications

Specification
MediaStream Recording # dom-mediarecorder-requestdata

Browser compatibility

	desktop					mobile
	Chrome	Edge	Firefox	Opera	Safari	Chrome Android	Firefox for Android	Opera Android	Safari on iOS	Samsung Internet	WebView Android	WebView on iOS
`requestData`	Chrome – Full support Chrome 49 (Release date: 2016-03-02) footnote Full support	Edge – Full support Edge 79 (Release date: 2020-01-15) footnote Full support	Firefox – Full support Firefox 25 (Release date: 2013-10-29) footnote Full support	Opera – Full support Opera 36 (Release date: 2016-03-15) footnote Full support	Safari – Full support Safari 14.1 (Release date: 2021-04-26) footnote Full support	Chrome Android – Full support Chrome Android 49 (Release date: 2016-03-09) footnote Full support	Firefox for Android – Full support Firefox for Android 25 (Release date: 2013-10-29) footnote Full support	Opera Android – Full support Opera Android 36 (Release date: 2016-03-31) footnote Full support	Safari on iOS – Full support Safari on iOS 14 (Release date: 2020-09-16) footnote Full support	Samsung Internet – Full support Samsung Internet 5 (Release date: 2016-12-15) footnote Full support	WebView Android – Full support WebView Android 49 (Release date: 2016-03-09) footnote Full support	WebView on iOS – Full support WebView on iOS 14 (Release date: 2020-09-16) footnote Full support

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Full support: Full support

MediaRecorder: requestData() method

Legend