Web/API/IdleDeadline

The IdleDeadline interface is used as the data type of the input parameter to idle callbacks established by calling Window.requestIdleCallback(). It offers a method, timeRemaining(), which lets you determine how much longer the user agent estimates it will remain idle and a property, didTimeout, which lets you determine if your callback is executing because its timeout duration expired.

To learn more about how request callbacks work, see Collaborative Scheduling of Background Tasks.

Properties

IdleDeadline.didTimeout Read only: A Boolean whose value is true if the callback is being executed because the timeout specified when the idle callback was installed has expired.

Methods

IdleDeadline.timeRemaining(): Returns a DOMHighResTimeStamp, which is a floating-point value providing an estimate of the number of milliseconds remaining in the current idle period. If the idle period is over, the value is 0. Your callback can call this repeatedly to see if there's enough time left to do more work before returning.

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
`IdleDeadline`	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
`didTimeout`	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
`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.