This is an experimental technology
Check the Browser compatibility table carefully before using this in production.

The getOutputTimestamp() property of the AudioContext interface returns a new AudioTimestamp object containing two correlated context's audio stream position values.

The two values are as follows:

  • The AudioTimestamp.contextTime member contains the time of the sample frame which is currently being rendered by the audio output device (i.e., output audio stream position), in the same units and origin as context's AudioContext.currentTime
  • The AudioTimestamp.performanceTime member contains the time, estimating the moment when the sample frame corresponding to the stored contextTime value was rendered by the audio output device, in the same units and origin as


var timestamp = AudioContext.getOutputTimestamp()




An AudioTimestamp, which has the following properties.

  • contextTime: A point in the time coordinate system of the currentTime for the BaseAudioContext.
  • performanceTime: A point in the time coordinate system of a Performance interface.


Specification Status Comment
Web Audio API
The definition of 'getOutputTimestamp()' in that specification.
Working Draft Initial definition.

Browser Compatibility

Update compatibility data on GitHub
ChromeEdgeFirefoxInternet ExplorerOperaSafariAndroid webviewChrome for AndroidEdge MobileFirefox for AndroidOpera for AndroidiOS SafariSamsung Internet
Basic support
Chrome Full support 57Edge ? Firefox No support NoIE No support NoOpera Full support 44Safari No support NoWebView Android Full support 57Chrome Android Full support 57Edge Mobile ? Firefox Android No support NoOpera Android Full support 44Safari iOS No support NoSamsung Internet Android Full support 7.0


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.

Document Tags and Contributors

Contributors to this page: fscholz, chrisdavidmills, david_ross, jpmedley
Last updated by: fscholz,