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This feature has been removed from the Web standards. Though some browsers may still support it, it is in the process of being dropped. Avoid using it and update existing code if possible; see the compatibility table at the bottom of this page to guide your decision. Be aware that this feature may cease to work at any time.


The MediaRecorder.onwarning event handler (part of the MediaRecorder API) handles the recordingwarning event, allowing you to run code in response to non-fatal errors being thrown during media recording via a MediaRecorder, which don't halt recording.


MediaRecorder.onwarning = function(event) { ... }
MediaRecorder.addEventListener('warning', function(event) { ... })



  mediaRecorder.onwarning = function(e) {
    console.log("A warning has been raised: " + e.message);



Contains information about the error that occurred.


Specification Status Comment
MediaStream Recording Working Draft Initial definition

Browser compatibility

Feature Chrome Firefox (Gecko) Internet Explorer Opera Safari (WebKit)
Basic support 47[2] 25.0 (25.0) No support No support No support
Feature Android Android Webview Firefox Mobile (Gecko) Firefox OS IE Phone Opera Mobile Safari Mobile Chrome for Android
Basic support No support No support 25.0 (25.0) 1.3[1] No support No support No support No support

[1] The intial Firefox OS implementation only supported audio recording.

[2] To try this feature on Chrome, enable Experimental Web Platform features from chrome://flags . Currently only video is supported, not audio.

See also

Document Tags and Contributors

 Contributors to this page: miguelao, jpmedley, Sebastianz, chrisdavidmills, teoli, kscarfone
 Last updated by: miguelao,