/Web APIs


The DedicatedWorkerGlobalScope object (the Worker global scope) is accessible through the self keyword. Some additional global functions, namespaces objects, and constructors, not typically associated with the worker global scope, but available on it, are listed in the JavaScript Reference. See also: Functions available to workers.

EventTarget WorkerGlobalScope DedicatedWorkerGlobalScope

Instance properties

This interface inherits properties from the WorkerGlobalScope interface, and its parent EventTarget.

DedicatedWorkerGlobalScope.name Read only

The name that the Worker was (optionally) given when it was created using the Worker() constructor. This is mainly useful for debugging purposes.

Instance properties inherited from WorkerGlobalScope

DedicatedWorkerGlobalScope.caches Read only

Returns the CacheStorage object associated with the current context. This object enables functionality such as storing assets for offline use, and generating custom responses to requests.

DedicatedWorkerGlobalScope.console Read only Non-standard

Returns the console associated with the worker.

DedicatedWorkerGlobalScope.fonts Read only

Returns the FontFaceSet associated with the worker.

DedicatedWorkerGlobalScope.indexedDB Read only

Provides a mechanism for applications to asynchronously access capabilities of indexed databases; returns an IDBFactory object.

DedicatedWorkerGlobalScope.isSecureContext Read only

Returns a boolean indicating whether the current context is secure (true) or not (false).

DedicatedWorkerGlobalScope.location Read only

Returns the WorkerLocation associated with the worker. WorkerLocation is a specific location object, mostly a subset of the Location for browsing scopes, but adapted to workers.

DedicatedWorkerGlobalScope.navigator Read only

Returns the WorkerNavigator associated with the worker. WorkerNavigator is a specific navigator object, mostly a subset of the Navigator for browsing scopes, but adapted to workers.

DedicatedWorkerGlobalScope.origin Read only

Returns the global object's origin, serialized as a string.

DedicatedWorkerGlobalScope.performance Read only

Returns the Performance object associated with the worker, which is a regular performance object, but with a subset of its properties and methods available.

DedicatedWorkerGlobalScope.scheduler Read only

Returns the Scheduler object associated with the current context. This is the entry point for using the Prioritized Task Scheduling API.


Returns an object reference to the DedicatedWorkerGlobalScope object itself.

Instance methods

This interface inherits methods from the WorkerGlobalScope interface, and its parent EventTarget.


Discards any tasks queued in the WorkerGlobalScope's event loop, effectively closing this particular scope.


Sends a message — which can consist of any JavaScript object — to the parent document that first spawned the worker.

Inherited from WorkerGlobalScope


Decodes a string of data which has been encoded using base-64 encoding.


Creates a base-64 encoded ASCII string from a string of binary data.


Cancels a callback scheduled by requestAnimationFrame.


Cancels the repeated execution set using setInterval.


Cancels the repeated execution set using setTimeout.

DedicatedWorkerGlobalScope.dump() Deprecated Non-standard

Writes a message to the console.


Imports one or more scripts into the worker's scope. You can specify as many as you'd like, separated by commas. For example: importScripts('foo.js', 'bar.js');


Requests the browser to execute a callback function before painting the next frame.


Schedules the execution of a function every X milliseconds.


Sets a delay for executing a function.



Fired when the worker receives a message from its parent.


Fired when a worker receives a message that can't be deserialized.


Browser compatibility

Desktop Mobile
Chrome Edge Firefox Internet Explorer Opera Safari WebView Android Chrome Android Firefox for Android Opera Android Safari on IOS Samsung Internet
DedicatedWorkerGlobalScope 4 12 3.5 10 10.6 4 4.4 18 4 11 5 1.0
cancelAnimationFrame 69 79 99 No 56 16.4 67 69 99 48 16.4 10.0
close 4 12 3.5 10 10.6 4 4.4 18 4 11 5 1.0
message_event 4 12 3.5 10 10.6 4 ≤37 18 4 11.5 5 1.0
messageerror_event 60 18 57 No 47
16.4See bug 171216.
60 60 57 47
16.4See bug 171216.
name 70 18 55 No 57 12.1 70 70 55 49 12.2 10.0
postMessage 4 12 3.5 10 10.6 4 4.4 18 4 11 5 1.0
requestAnimationFrame 69 79 99 No 56 16.4 67 69 99 48 16.4 10.0
rtctransform_event No No No No No 15.4 No No No No 15.4 No

See also

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