This is an experimental technology
Check the Browser compatibility table carefully before using this in production.

The onmessage property of the ServiceWorkerContainer interface is an event handler fired whenever a message event occurs — when incoming messages are received to the ServiceWorkerContainer object (e.g., via a Client.postMessage() call).

Note: Messages received from service worker contexts (e.g. as the event object of onmessage) are represented by MessageEvent objects in modern browsers, for consistency with other web messaging features. (They used to be represented by ServiceWorkerMessageEvent objects, which have now been deprecated.)


serviceWorkerContainer.onmessage = function(messageevent) { ... }


navigator.serviceWorker.onmessage = function(messageevent) {
  console.log(`received data: ${}`);


Specification Status Comment
Service Workers
The definition of 'ServiceWorkerContainer: onmessage' in that specification.
Working Draft Initial definition.

Browser compatibility

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