The read-only droppedVideoFrames property of the VideoPlaybackQuality interface returns the number of video frames which have been dropped rather than being displayed since the last time the media was loaded into the HTMLVideoElement.


value = videoPlaybackQuality.droppedVideoFrames;


An unsigned 64-bit value indicating the number of frames that have been dropped since the last time the media in the <video> element was loaded or reloaded. This information can be used to determine whether or not to downgrade the video stream to avoid dropping frames.

Frames are typically dropped either before or after decoding them, when it's determined that it will not be possible to draw them to the screen at the correct time.



This example calls getVideoPlaybackQuality() to obtain a VideoPlaybackQuality object, then determines what percentage of frames have been dropped. That value is then presented in an element for the user's reference.

var videoElem = document.getElementById("my_vid");
var percentElem = document.getElementById("percent");
var quality = videoElem.getVideoPlaybackQuality();

var dropPercent = (quality.droppedVideoFrames/quality.totalVideoFrames)*100;
percentElem.innerText = Math.trunc(dropPercent).toString(10);


Specification Status Comment
Media Playback Quality
The definition of 'VideoPlaybackQuality.droppedVideoFrames' in that specification.
Editor's Draft Initial definition.

Browser compatibility

Update compatibility data on GitHub
ChromeEdgeFirefoxInternet ExplorerOperaSafariAndroid webviewChrome for AndroidFirefox for AndroidOpera for AndroidSafari on iOSSamsung Internet
Chrome Full support 23Edge Full support 12Firefox Full support 42
Full support 42
No support 25 — 42
Notes Disabled
Notes Limited support to an allowed list of sites, for example YouTube, Netflix, and other popular streaming sites. The limitation was removed when Media Source Extensions was enabled by default in Firefox 42.
Disabled From version 25 until version 42 (exclusive): this feature is behind the media.mediasource.enabled preference. To change preferences in Firefox, visit about:config.
IE Full support 11
Full support 11
Notes Only works on Windows 8+.
Opera Full support 15Safari Full support 8WebView Android Full support 4.4.3Chrome Android ? Firefox Android No support NoOpera Android Full support 14Safari iOS No support NoSamsung Internet Android ?


Full support  
Full support
No support  
No support
Compatibility unknown  
Compatibility unknown
Experimental. Expect behavior to change in the future.
Experimental. Expect behavior to change in the future.
See implementation notes.
See implementation notes.
User must explicitly enable this feature.
User must explicitly enable this feature.

See also