ServiceWorkerGlobalScope: messageerror event

Secure context: This feature is available only in secure contexts (HTTPS), in some or all supporting browsers.

Note: This feature is only available in Service Workers.

The messageerror event of the ServiceWorkerGlobalScope interface occurs when incoming messages can't be deserialized.

This event is not cancelable and does not bubble.


Use the event name in methods like addEventListener(), or set an event handler property.

addEventListener("messageerror", (event) => {});

onmessageerror = (event) => {};

Event type

Event properties

Inherits properties from its parent, ExtendableEvent. Read only

Returns the event's data. It can be any data type. If dispatched in messageerror event, the property will be null.

ExtendableMessageEvent.origin Read only

Returns the origin of the Client that sent the message.

ExtendableMessageEvent.lastEventId Read only

Represents, in server-sent events, the last event ID of the event source.

ExtendableMessageEvent.source Read only

Returns a reference to the Client object that sent the message.

ExtendableMessageEvent.ports Read only

Returns the array containing the MessagePort objects representing the ports of the associated message channel.


In the below example a page gets a handle to the ServiceWorker object via, and then calls its postMessage() function.

// main.js
if (navigator.serviceWorker) {

  navigator.serviceWorker.addEventListener("message", (event) => {
    // event is a MessageEvent object
    console.log(`The service worker sent me a message: ${}`);

  navigator.serviceWorker.ready.then((registration) => {"Hi service worker");

The service worker can listen for the message deserialization error by listening to the messageerror event:

// service-worker.js
self.addEventListener("messageerror", (event) => {
  // event is an ExtendableMessageEvent object
  console.error("Message deserialization failed");

Alternatively, the script can listen for the message deserialization error using onmessageerror:

// service-worker.js
self.onmessageerror = (event) => {
  // event is an ExtendableMessageEvent object
  console.error("Message deserialization failed");


Service Workers
# eventdef-serviceworkerglobalscope-messageerror
Service Workers
# dom-serviceworkerglobalscope-onmessageerror

Browser compatibility

BCD tables only load in the browser

See also