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This is an experimental technology
Because this technology's specification has not stabilized, check the compatibility table for usage in various browsers. Also note that the syntax and behavior of an experimental technology is subject to change in future versions of browsers as the specification changes.

The installing property of the ServiceWorkerRegistration interface returns a service worker whose ServiceWorker.state is installing. This property is initially set to null.

Note: This feature is available in Web Workers.


sw = ServiceWorker.installing 


A ServiceWorker object, if it is currently in an installing state.


Specification Status Comment
Service Workers
The definition of 'ServiceWorkerRegistration.installing' in that specification.
Working Draft Initial definition.

Browser compatibility

Feature Chrome Firefox (Gecko) Internet Explorer Opera Safari (WebKit)
Basic support 40.0 44.0 (44.0)[1] No support ? No support
Available in web workers (Yes) 44.0 (44.0)[1] No support ? No support
Feature Android Android Webview Firefox Mobile (Gecko) Firefox OS IE Mobile Opera Mobile Safari Mobile Chrome for Android
Basic support No support No support 44.0 (44.0) (Yes) No support ? No support 40.0
Available in web workers ? ? (Yes) ? No support ? No support ?

[1] Service workers (and Push) have been disabled in the Firefox 45 Extended Support Release (ESR.)

See also

Document Tags and Contributors

 Contributors to this page: chrisdavidmills, jpmedley, fscholz, kscarfone
 Last updated by: chrisdavidmills,