name

A string representing the name of the mark. Must not be the same name as one of the properties of the deprecated PerformanceTiming interface.

markOptions Optional

An object for specifying a timestamp and additional metadata for the mark.

detail Optional

Arbitrary metadata to include in the mark. Defaults to null. Must be structured-cloneable.

startTime Optional

performance.now().

The PerformanceMark entry that was created.

• PerformanceTiming interface. See the example below.
• TypeError: Thrown if startTime is negative.

The following example uses mark() to create named PerformanceMark object that has been created.

performance.mark("login-started");
performance.mark("login-started");
performance.mark("login-finished");
performance.mark("form-sent");

const videoMarker = performance.mark("video-loaded");

The performance mark is configurable using the markOptions object where you can put additional information in the detail property, which can be of any type.

performance.mark("login-started", {
  detail: "Login started using the login button in the top menu.",
});

performance.mark("login-started", {
  detail: { htmlElement: myElement.id },
});

The default timestamp of the mark() method is performance.now(). You can set it to a different time using the startTime option in markOptions.

performance.mark("start-checkout", {
  startTime: 20.0,
});

performance.mark("login-button-pressed", {
  startTime: myEvent.timeStamp,
});

Note in order to maintain backwards compatibility, names that are part of the deprecated PerformanceTiming interface can't be used. The following example throws:

performance.mark("navigationStart");
/ SyntaxError: "navigationStart" is part of
/ the PerformanceTiming interface,
/ and cannot be used as a mark name