Web/API/AbstractWorker/onerror

The AbstractWorker.onerror property of the AbstractWorker interface represents an EventHandler, that is a function to be called when the error event occurs and bubbles through the Worker.

Syntax

myWorker.onerror = function() { ... };

Example

The following code snippet shows creation of a Worker object using the Worker() constructor and setting up of an onerror handler on the resulting object:

var myWorker = new Worker('worker.js');

myWorker.onerror = function() {
  console.log('There is an error with your worker!');
}

Specifications

Specification	Status	Comment
HTML Living StandardThe definition of 'AbstractWorker.onerror' in that specification.	Living Standard

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
`onerror`	Chrome Full support 4	Edge Full support 12	Firefox Full support 3.5	IE Full support 10	Opera Full support 10.6	Safari Full support 4	WebView Android Full support 4.4	Chrome Android Full support 18	Firefox Android Full support 4	Opera Android Full support 11	Safari iOS Full support 5.1	Samsung Internet Android Full support 1.0

Legend

Full support: Full support

Cross-origin worker error behaviour

In earlier browser versions, trying to load a cross-origin worker script threw a SecurityError; in newer browsers an error event is thrown instead due to a spec change. Find out more information on how to deal with this in Loading cross-origin worker now fires error event instead of throwing; worker in sandboxed iframe no longer allowed.