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Cancels a timeout previously established by calling setTimeout().

Syntax

window.clearTimeout(timeoutID)

Parameters

timeoutID
The identifier of the timeout you want to cancel. This ID was returned by the corresponding call to setTimeout().

It's worth noting that the pool of IDs used by setTimeout() and setInterval() are shared, which means you can technically use clearTimeout() and clearInterval() interchangeably. However, for clarity, you should avoid doing so.

Example

Run the script below in the context of a web page and click on the page once. You'll see a message popping up in a second. If you click the page multiple times in one second, the alert only appears once.

var alarm = {
  remind: function(aMessage) {
    alert(aMessage);
    this.timeoutID = undefined;
  },

  setup: function() {
    if (typeof this.timeoutID === "number") {
      this.cancel();
    }

    this.timeoutID = window.setTimeout(function(msg) {
      this.remind(msg);
    }.bind(this), 1000, "Wake up!");
  },

  cancel: function() {
    window.clearTimeout(this.timeoutID);
    this.timeoutID = undefined;
  }
};
window.onclick = function() { alarm.setup(); };

Notes

Passing an invalid ID to clearTimeout() silently does nothing; no exception is thrown.

Specifications

Specification Status Comment
WHATWG HTML Living Standard
The definition of 'clearTimeout()' in that specification.
Living Standard  

See also

Document Tags and Contributors

 Last updated by: DLuPi,