This feature is obsolete. Although it may still work in some browsers, its use is discouraged since it could be removed at any time. Try to avoid using it.

The Document.fullscreen read-only property reports whether or not the document is currently displaying content in fullscreen mode.

Although this property is read-only, it will not throw if it is modified (even in strict mode); the setter is a no-operation and it will be ignored.

This property is deprecated; test if Document.fullscreenElement is not null instead.


var isFullScreen = document.fullscreen;

Return value

  • A Boolean that is true if the document is being displayed in fullscreen mode; otherwise it's false.


function isDocumentInFullScreenMode() {
  // Better: use fullscreenElement method!
  return document.fullscreen;  


Specification Status Comment
Fullscreen API
The definition of 'Document.fullscreen' in that specification.
Living Standard Initial definition (as an obsolete property).

Browser compatibility

FeatureChromeEdgeFirefoxInternet ExplorerOperaSafari
Basic support Yes1 ?



? ? Yes1
FeatureAndroid webviewChrome for AndroidEdge mobileFirefox for AndroidOpera AndroidiOS SafariSamsung Internet
Basic support ? Yes1 ?



? ? ?

1. Supported as webkitIsFullScreen.

2. Supported as mozFullScreen.

3. From version 49: this feature is behind the full-screen-api.unprefix.enabled preference (needs to be set to true). To change preferences in Firefox, visit about:config.

4. Supported as mozFullSreen.

See also

Document Tags and Contributors

Last updated by: fscholz,