WindowEventHandlers.onunhandledrejection

The onunhandledrejection property of the WindowEventHandlers mixin is the EventHandler for processing unhandledrejection events. These events are raised for unhandled Promise rejections.

Syntax

window.onunhandledrejection = function;

Value

function is an EventHandler or function to call when unhandledrejection events are received by the window. The event handler receives as an input parameter as a PromiseRejectionEvent.

Examples

This example simply logs unhandled rejections' reason values to the console.

window.onunhandledrejection = function(e) {
  console.log(e.reason);
}

Specifications

Specification Status Comment
HTML Living Standard
The definition of 'onunhandledrejection' in that specification.
Living Standard Initial definition.

Browser compatibility

Update compatibility data on GitHub
DesktopMobile
ChromeEdgeFirefoxInternet ExplorerOperaSafariAndroid webviewChrome for AndroidEdge MobileFirefox for AndroidOpera for AndroidSafari on iOSSamsung Internet
Basic supportChrome Full support 49Edge Full support YesFirefox No support No
Notes
No support No
Notes
Notes Firefox implements the PromiseRejectionEvent interface if you go to about:config and set the dom.promise_rejection_events.enabled pref to true. However, Firefox doesn't yet actually send the unhandledrejection or understand rejectionhandled events. Completing the implementation will be addressed in bug 1362272.
IE No support NoOpera No support NoSafari No support NoWebView Android No support NoChrome Android No support NoEdge Mobile Full support YesFirefox Android No support No
Notes
No support No
Notes
Notes Firefox implements the PromiseRejectionEvent interface if you go to about:config and set the dom.promise_rejection_events.enabled pref to true. However, Firefox doesn't yet actually send the unhandledrejection or understand rejectionhandled events. Completing the implementation will be addressed in bug 1362272.
Opera Android No support NoSafari iOS No support NoSamsung Internet Android ?

Legend

Full support  
Full support
No support  
No support
Compatibility unknown  
Compatibility unknown
See implementation notes.
See implementation notes.

Document Tags and Contributors

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