Web/API/Performance/measure

The measure() method creates a named timestamp in the browser's performance entry buffer between marks, the navigation start time, or the current time. When measuring between two marks, there is a start mark and end mark, respectively. The named timestamp is referred to as a measure.

The measure can be retrieved by one of the Performance interfaces: (getEntries(), getEntriesByName() or getEntriesByType()).

The measure's performance entry will have the following property values:

entryType - set to "measure".
name - set to the "name" given when the measure was created.
startTime - set to the start mark timestamp.
duration - set to a DOMHighResTimeStamp that is the duration of the measure (typically, the end mark timestamp minus the start mark timestamp).

Note: This feature is available in Web Workers.

Syntax

performance.measure(name);
performance.measure(name, startMark);
performance.measure(name, startMark, endMark);
performance.measure(name, undefined, endMark);

Arguments

name: A DOMString representing the name of the measure.
startMark Optional: A DOMString representing the name of the measure's starting mark. May also be the name of a PerformanceTiming property. If it is omitted, then the start time will be the navigation start time.
endMark Optional: A DOMString representing the name of the measure's ending mark. May also be the name of a PerformanceTiming property. If it is omitted, then the current time is used.

Return value

void

Example

The following example shows how measure() is used to create a new measure performance entry in the browser's performance entry buffer.

const markerNameA = "example-marker-a"
const markerNameB = "example-marker-b"

// Run some nested timeouts, and create a PerformanceMark for each.
performance.mark(markerNameA);
setTimeout(function() {
  performance.mark(markerNameB);
  setTimeout(function() {

    // Create a variety of measurements.
    performance.measure("measure a to b", markerNameA, markerNameB);
    performance.measure("measure a to now", markerNameA);
    performance.measure("measure from navigation start to b", undefined, markerNameB);
    performance.measure("measure from the start of navigation to now");

    // Pull out all of the measurements.
    console.log(performance.getEntriesByType("measure"));

    // Finally, clean up the entries.
    performance.clearMarks();
    performance.clearMeasures();
  }, 1000);
}, 1000);

Specifications

Specification	Status	Comment
User Timing Level 2The definition of 'measure()' in that specification.	Working Draft	Clarifies `measure()` processing model.
User TimingThe definition of 'measure()' in that specification.	Recommendation	Basic definition.

Browser compatibility

Update compatibility data on GitHub

	Desktop						Mobile
	Chrome	Edge	Firefox	Internet Explorer	Opera	Safari	Android webview	Chrome for Android	Firefox for Android	Opera for Android	Safari on iOS	Samsung Internet
`measure`	Chrome Full support 28 Full support 28 No support 25 — 28 Prefixed' Prefixed' Implemented with the vendor prefix: webkit	Edge Full support 12	Firefox Full support 41	IE Full support 10	Opera Full support 33	Safari Full support 11	WebView Android Full support 46	Chrome Android Full support 28 Full support 28 No support 25 — 28 Prefixed' Prefixed' Implemented with the vendor prefix: webkit	Firefox Android Full support 42	Opera Android Full support 33	Safari iOS Full support 11	Samsung Internet Android Full support 1.5

Legend

Full support: Full support
Requires a vendor prefix or different name for use.': Requires a vendor prefix or different name for use.

performance.measure() by Mozilla Contributors is licensed under CC-BY-SA 2.5.