PerformanceObserver

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 feature is available in Web Workers

Constructor

PerformanceObserver(): Creates and returns a new PerformanceObserver object.

Properties

PerformanceObserver.supportedEntryTypesRead only: Returns an array of the entryType values supported by the user agent.

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.
PerformanceObserver.takeRecords(): Returns the current list of performance entries stored in the performance observer, emptying it out.

Example

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

Specifications

Specification
Performance Timeline Level 2 (Performance Timeline 2) # dom-performanceobserver

Browser compatibility

	Desktop						Mobile
	Chrome	Edge	Firefox	Internet Explorer	Opera	Safari	WebView Android	Chrome Android	Firefox for Android	Opera Android	Safari on IOS	Samsung Internet
`PerformanceObserver`	52	79	57	No	39	11	52	52	57	41	11	6.0
`PerformanceObserver`	52	79	57	No	39	11	52	52	57	41	11	6.0
`disconnect`	52	79	57	No	39	11	52	52	57	41	11	6.0
`observe`	52	79	57	No	39	11	52	52	57	41	11	6.0
`supportedEntryTypes`	73	79	68	No	Yes	12.1	73	73	68	Yes	12.2	11.0
`takeRecords`	65	79	60	No	Yes	No	65	65	60	Yes	No	9.0
`worker_support`	62	≤79	57	No	49	11	62	62	57	46	11	8.0