Performance.measure()

The measure() method creates a named timestamp in the browser's performance entry buffer between two specified marks (known as the 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 interface's getEntries*() methods (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 timestamp when measure() was called.
• 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, startMark, 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.

endMark Optional

A DOMString representing the name of the measure's ending mark. May also be the name of a PerformanceTiming property.

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.

// Start with one mark.
performance.mark("mySetTimeout-start");
// Wait some time.
setTimeout(function() {
  // Mark the end of the time.
  performance.mark("mySetTimeout-end");
  // Measure between the two different markers.
  performance.measure(
    "mySetTimeout",
    "mySetTimeout-start",
    "mySetTimeout-end"
  );
  // Get all of the measures out.
  // In this case there is only one.
  var measures = performance.getEntriesByName("mySetTimeout");
  var measure = measures[0];
  console.log("setTimeout milliseconds:", measure.duration)
  // Clean up the stored markers.
  performance.clearMarks();
  performance.clearMeasures();
}, 1000);

Specifications

Browser compatibility