Web/API/IdleDeadline/didTimeout

The read-only didTimeout property on the IdleDeadline interface is a Boolean value which indicates whether or not the idle callback is being invoked because the timeout interval specified when Window.requestIdleCallback() was called has expired.

If didTimeout is true, the IdleDeadline object's timeRemaining() method will return approximately 0.

Idle callbacks support the concept of a timeout in order to ensure that whatever task they're meant to perform actually happens, even if the user agent never has enough idle time available. Your callback will typically check the value of didTimeout if it needs to perform an action even if the browser is too busy to grant you the time; you should react by performing the needed task or, ideally, a minimal amount of work that can be done to keep things moving along, then schedule a new callback to try again to get the rest of the work done.

Syntax

var timedOut = IdleDeadline.didTimeout;

Value

A Boolean which is true if the callback is running due to the callback's timeout period elapsing or false if the callback is running because the user agent is idle and is offering time to the callback.

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
`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

Legend

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