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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 PerformanceObserver interface is used to observe performance measurement events and be notified of new performance entries as they are recorded in the browser's performance timeline.

Note: this interface is exposed to Window and Worker.

Constructor

PerformanceObserver()
Creates a PerformanceObserver object.

Methods

PerformanceObserver.observe()
Specifies the set of entry types to observe. The performance observer's callback function will be invoked when a performance entry is recorded for one of the specified entryTypes
PerformanceObserver.disconnect()
Stops the performance observer callback from receiving performance entries.

Example

function perf_observer(list, observer) { 
   // Process the "measure" event 
} 
var observer2 = new PerformanceObserver(perf_observer); 
observer2.observe({entryTypes: ["measure"]});

Specifications

Specification Status Comment
Performance Timeline Time Level 2
The definition of 'PerformanceObserver' in that specification.
Editor's Draft Initial definition of PerformanceObserver interface.

Browser compatibility

Feature Chrome Firefox (Gecko) Internet Explorer Opera Safari (WebKit)
Basic support 52.0 49 (49)[1] No support 39 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 49.0 (49)[1] No support No support

39

No support 52.0

[1] Only activated in Nightly builds. Controlled by the dom.enable_performance_observer preference.

Document Tags and Contributors

 Contributors to this page: jpmedley, teoli, rolfedh, AFBarstow
 Last updated by: jpmedley,