MediaDeviceInfo

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This is an experimental technology
Because this technology's specification has not stabilized, check the compatibility table for usage in various browsers. Also note that the syntax and behavior of an experimental technology is subject to change in future versions of browsers as the specification changes.

The MediaDevicesInfo interface contains information on the available media input and output devices.

Properties

MediaDeviceInfo.deviceIdRead only
Returns a DOMString that is an identifier for the represented device that is persisted across sessions. It is un-guessable by other applications and unique to the origin of the calling application. It is reset when the user clears cookies (for Private Browsing, a different identifier is used that is not persisted across sessions).
MediaDeviceInfo.groupIdRead only
Returns a DOMString that is a group identifier. Two devices have the same group identifier if they belong to the same physical device — for example a monitor with both a built-in camera and a microphone.
MediaDeviceInfo.kindRead only
Returns an enumerated value that is either "videoinput", "audioinput" or "audiooutput".
MediaDeviceInfo.labelRead only
Returns a DOMString that is a label describing this device (for example "External USB Webcam"). Only available during active MediaStream use or when persistent permissions have been granted.

Methods

None.

Example

Here's an example of using mediaDevices.enumerateDevices().

if (!navigator.mediaDevices || !navigator.mediaDevices.enumerateDevices) {
  console.log("enumerateDevices() not supported.");
  return;
}
// List cameras and microphones.
navigator.mediaDevices.enumerateDevices()
.then(function(devices) {
  devices.forEach(function(device) {
    console.log(device.kind + ": " + device.label +
                " id = " + device.deviceId);
  });
})
.catch(function(err) {
  console.log(err.name + ": " + error.message);
});

This might produce:

videoinput: id = csO9c0YpAf274OuCPUA53CNE0YHlIr2yXCi+SqfBZZ8=
audioinput: id = RKxXByjnabbADGQNNZqLVLdmXlS0YkETYCIbg+XxnvM=
audioinput: id = r2/xw1xUPIyZunfV1lGrKOma5wTOvCkWfZ368XCndm0=

or if one or more MediaStreams are active or persistent permissions are granted:

videoinput: FaceTime HD Camera (Built-in) id=csO9c0YpAf274OuCPUA53CNE0YHlIr2yXCi+SqfBZZ8=
audioinput: default (Built-in Microphone) id=RKxXByjnabbADGQNNZqLVLdmXlS0YkETYCIbg+XxnvM=
audioinput: Built-in Microphone id=r2/xw1xUPIyZunfV1lGrKOma5wTOvCkWfZ368XCndm0=

Specifications

Specification Status Comment
Media Capture and Streams
The definition of 'MediaDevicesInfo' in that specification.
Editor's Draft Initial definition

Browser compatibility

Feature Chrome Edge Firefox (Gecko) Internet Explorer Opera Safari (WebKit)
Basic support 55.0[1] (Yes) 39 No support ?[2] No support
Feature Android Android Webview Edge Firefox Mobile (Gecko) Firefox OS (Gecko) IE Phone Opera Mobile Safari Mobile Chrome for Android
Basic support No support ? (Yes) 39 2.5 No support ?[2] No support ?

[1] For earlier versions, this interface is available through the adapter.js polyfill.

[2] This interface is available in Opera through the adapter.js polyfill.

See also

  • WebRTC - the introductory page to the API

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