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 also 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).

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

entry

The PerformanceMeasure entry that was created.

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 navigation start 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

Browser compatibility