This is an experimental technology
Check the Browser compatibility table carefully before using this in production.

The webdriver read-only property of the navigator interface indicates whether the user agent is controlled by automation.

It defines a standard way for co-operating user agents to inform the document that it is controlled by WebDriver, for example so that alternate code paths can be triggered during automation.

The navigator.webdriver property is true when in:

The --enable-automation or the --headless flag is used.
The marionette.enabled preference or --marionette flag is passed.


var isAutomated = navigator.webdriver


A Boolean


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

Browser compatibility

Update compatibility data on GitHub
ChromeEdgeFirefoxInternet ExplorerOperaSafariAndroid webviewChrome for AndroidEdge MobileFirefox for AndroidOpera for AndroidSafari on iOSSamsung Internet
Basic support
Chrome Full support 63Edge ? Firefox ? IE ? Opera Full support 50Safari ? WebView Android ? Chrome Android Full support 63Edge Mobile ? Firefox Android ? Opera Android Full support 50Safari iOS ? Samsung Internet Android ?


Full support  
Full support
Compatibility unknown  
Compatibility unknown
Experimental. Expect behavior to change in the future.
Experimental. Expect behavior to change in the future.

Document Tags and Contributors

Contributors to this page: mdnwebdocs-bot, mfuji09, fscholz, ato, jpmedley
Last updated by: mdnwebdocs-bot,