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.


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 (en-US) property is true, this method returns zero.


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


Specification Status Comment
Cooperative Scheduling of Background Tasks Proposed Recommendation

Browser compatibility

BCD tables only load in the browser

See also