On the standards track: Yes
Is Experimental: No
Is Deprecated: No
In Chrome version 9 on 2011-02-03 Note: Before Chrome 50, this property returned the deprecated child DOMSettableTokenList instead of DOMTokenList.
In Chrome Android version 18 on 2012-06-27 Note: Before Chrome Android 50, this property returned the deprecated child DOMSettableTokenList instead of DOMTokenList.
In Edge version 14 on 2016-08-02
In Firefox version 4 on 2011-03-22
In Firefox for Android version 4 on 2011-03-29
Not in Internet Explorer
In Quest Browser version 5.0 on undefined Note: Before Quest Browser 5.0, this property returned the deprecated child DOMSettableTokenList instead of DOMTokenList.
In Opera version 15 on 2013-07-02 Note: Before Opera 37, this property returned the deprecated child DOMSettableTokenList instead of DOMTokenList.
In Opera Android version 14 on 2013-05-21 Note: Before Opera Android 37, this property returned the deprecated child DOMSettableTokenList instead of DOMTokenList.
In Safari version 5.1 on 2011-07-20
In Safari on iOS version 5 on 2011-10-12
In Samsung Internet version 1.0 on 2013-04-27 Note: Before Samsung Internet 5.0, this property returned the deprecated child DOMSettableTokenList instead of DOMTokenList.
In WebView Android version 3 on 2011-02-22 Note: Before Chrome 50, this property returned the deprecated child DOMSettableTokenList instead of DOMTokenList.
In WebView on iOS version 5 on 2011-10-12