Web/API/IdleDeadline/timeRemaining

This is an experimental technologyCheck the Browser compatibility table carefully before using this in production.

The timeRemaining() method on the IdleDeadline interface returns the estimated number of milliseconds remaining in the current idle period. The callback can call this method at any time to determine how much time it can continue to work before it must return. For example, if the callback finishes a task and has another one to begin, it can call timeRemaining() to see if there's enough time to complete the next task. If there isn't, the callback can just return immediately, or look for other work to do with the remaining time.

By the time timeRemaining() reaches 0, it is suggested that the callback should return control to the user agent's event loop.

Syntax

timeRemaining = IdleDeadline.timeRemaining();

Return value

A DOMHighResTimeStamp value (which is a floating-point number) representing the number of milliseconds the user agent estimates are left in the current idle period. The value is ideally accurate to within about 5 microseconds.

If the IdleDeadline object's didTimeout property is true, this method returns zero.

Example

See our complete example in the article Cooperative Scheduling of Background Tasks API.

Specifications

Specification	Status	Comment
Cooperative Scheduling of Background Tasks	Proposed Recommendation

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
`timeRemaining`	Chrome Full support 47	Edge Full support 79	Firefox Full support 55 Full support 55 Full support 53 Disabled' Disabled' From version 53: this feature is behind the `dom.requestIdleCallback.enabled` preference (needs to be set to `true`). To change preferences in Firefox, visit about:config.	IE No support No	Opera Full support 34	Safari No support No	WebView Android Full support 47	Chrome Android Full support 47	Firefox Android Full support 55 Full support 55 Full support 53 Disabled' Disabled' From version 53: this feature is behind the `dom.requestIdleCallback.enabled` preference (needs to be set to `true`). To change preferences in Firefox, visit about:config.	Opera Android Full support 34	Safari iOS No support No	Samsung Internet Android Full support 5.0

Legend

Full support: Full support
No support: No support
User must explicitly enable this feature.': User must explicitly enable this feature.