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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 BroadcastChannel.postMessage() sends a message, which can be of any kind of Object, to each listener in any browser context with the same origin. The message is transmitted as a message event targeted at each BroadcastChannel bound to the channel.

Note: This feature is available in Web Workers.


var str = channel.postMessage(object);


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

Browser compatibility

Feature Chrome Firefox (Gecko) Internet Explorer Opera Safari
Basic support 54.0 38 (38) No support 41 No support
Available in workers 54.0 38 (38) No support 41 No support
Feature Android Android Webview Firefox Mobile (Gecko) IE Mobile Opera Mobile Safari Mobile Chrome for Android
Basic support No support No support 38.0 (38) No support 41 No support 54.0
Available in workers No support No support 38.0 (38) No support 41 No support 54.0

See also

Document Tags and Contributors

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