Summary
The unload
event is raised when the window is unloading its content and resources. The resources removal is processed after the unload
event occurs.
Syntax
window.onunload = funcRef;
funcRef
is a reference to a function.
Notes
Using this event handler in your page prevents Firefox 1.5 from caching the page in the in-memory bfcache. See Using Firefox 1.5 caching for details.
Browsers equipped with pop-up window blockers will ignore all window.open()
method calls in onunload
event handler functions.
You can and should handle this event through window.addEventListener()
and the unload
event. More documentation is available there.
Specifications
Specification | Status | Comment |
---|---|---|
WHATWG HTML Living Standard The definition of 'GlobalEventHandlers' in that specification. |
Living Standard | |
HTML 5.1 The definition of 'GlobalEventHandlers' in that specification. |
Recommendation | |
HTML5 The definition of 'GlobalEventHandlers' in that specification. |
Recommendation |
Browser compatibility
Feature | Chrome | Edge | Firefox (Gecko) | Internet Explorer | Opera | Safari (WebKit) |
---|---|---|---|---|---|---|
Basic support | (Yes) | (Yes) | (Yes) | (Yes) | (Yes) | (Yes) |
Feature | Android | Edge | Firefox Mobile (Gecko) | IE Phone | Opera Mobile | Safari Mobile |
---|---|---|---|---|---|---|
Basic support | (Yes) | (Yes) | (Yes) | (Yes) | (Yes) | (Yes) |