The BroadcastChannel.postMessage() sends a message, which can be of any kind of Object, to each listener in any browsing 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
HTML Living Standard
The definition of 'BroadcastChannel.postmessage()' in that specification.
Living Standard Initial definition.

Browser compatibility

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ChromeEdgeFirefoxInternet ExplorerOperaSafariAndroid webviewChrome for AndroidFirefox for AndroidOpera for AndroidSafari on iOSSamsung Internet
postMessageChrome Full support 54Edge Full support ≤79Firefox Full support 38IE No support NoOpera Full support 41Safari No support NoWebView Android Full support 54Chrome Android Full support 54Firefox Android ? Opera Android Full support 41Safari iOS No support NoSamsung Internet Android Full support 6.0


Full support  
Full support
No support  
No support
Compatibility unknown  
Compatibility unknown

See also