performance.mark()

The mark() method creates a timestamp in the browser's performance entry buffer with the given name. The application defined timestamp can be retrieved by one of the Performance interface's getEntries*() methods (getEntries(), getEntriesByName() or getEntriesByType()).

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

• entryType - set to "mark".
• name - set to the "name" given when the mark was created.
• startTime - set to the timestamp when mark() was called.
• duration - set to "0" (a mark has no duration).

If the name given to this method already exists in the PerformanceTiming interface, SyntaxError is thrown.

Syntax

performance.mark(name);

Arguments

name

A DOMString representing the name of the mark.

Return value

void

 

Example

The following example shows how to use mark() to create and retrieve PerformanceMark entries.

// Create a bunch of marks.
performance.mark("squirrel");
performance.mark("squirrel");
performance.mark("monkey");
performance.mark("monkey");
performance.mark("dog");
performance.mark("dog");

// Get all of the PerformanceMark entries.
const allEntries = performance.getEntriesByType("mark");
console.log(allEntries.length);
// 6

// Get all of the "monkey" PerformanceMark entries.
const monkeyEntries = performance.getEntriesByName("monkey");
console.log(monkeyEntries.length);
// 2

// Clear out all of the marks.
performance.clearMarks();

Specifications

Browser compatibility