onpopstate is an event handler for the popstate event on the window.

A popstate event is dispatched to the window each time the active history entry changes between two history entries for the same document. If the activated history entry was created by a call to history.pushState(), or was affected by a call to history.replaceState(), the popstate event's state property contains a copy of the history entry's state object.

Note: calling history.pushState() or history.replaceState() won't trigger a popstate event. The popstate event is only triggered by performing a browser action, such as clicking on the back button (or calling history.back() in JavaScript), when navigating between two history entries for the same document.

Note: Browsers used to handle the popstate event differently on page load, but now they behave the same. Firefox never emitted a popstate event on page load. Chrome did until version 34, while Safari did until version 10.0.

Syntax

window.onpopstate = funcRef;
  • funcRef is a handler function.

The popstate event

For example, a page at http://example.com/example.html running the following code will generate alerts as indicated:

window.onpopstate = function(event) {
  alert("location: " + document.location + ", state: " + JSON.stringify(event.state));
};

history.pushState({page: 1}, "title 1", "?page=1");
history.pushState({page: 2}, "title 2", "?page=2");
history.replaceState({page: 3}, "title 3", "?page=3");
history.back(); // alerts "location: http://example.com/example.html?page=1, state: {"page":1}"
history.back(); // alerts "location: http://example.com/example.html, state: null
history.go(2);  // alerts "location: http://example.com/example.html?page=3, state: {"page":3}

Note that even though the original history entry (for http://example.com/example.html) has no state object associated with it, a popstate event is still fired, when we activate that entry after the second call to history.back().

Specification

Browser compatibility

Update compatibility data on GitHub
DesktopMobile
ChromeEdgeFirefoxInternet ExplorerOperaSafariAndroid webviewChrome for AndroidEdge MobileFirefox for AndroidOpera for AndroidiOS SafariSamsung Internet
Basic supportChrome Full support 5Edge Full support 12Firefox Full support 4IE Full support 10Opera Full support 11.5Safari Full support 6WebView Android ? Chrome Android Full support 18Edge Mobile ? Firefox Android Full support 4Opera Android Full support 12Safari iOS Full support 5.1Samsung Internet Android ?

Legend

Full support  
Full support
Compatibility unknown  
Compatibility unknown

See also

Document Tags and Contributors

Last updated by: chrisdavidmills,