On the standards track: Yes
Is Experimental: No
Is Deprecated: No
In Chrome version 1 on 2008-12-11
In Chrome Android version 18 on 2012-06-27
In Edge version 12 on 2015-07-29
In Firefox version 1 on 2004-11-09
In Firefox for Android version 4 on 2011-03-29
In Internet Explorer version 5 on 1999-03-18 Note: In Internet Explorer versions before 7, when both top and bottom are specified, the element position is overconstrained and the top property has precedence; the computed value of bottom is set to -top, while its specified value is ignored.
In Quest Browser version 5.0 on undefined
In Opera version 6 on 2001-12-18
In Opera Android version 14 on 2013-05-21
In Safari version 1 on 2003-06-23
In Safari on iOS version 1 on 2007-06-29
In Samsung Internet version 1.0 on 2013-04-27
In WebView Android version 4.4 on 2013-12-09
In WebView on iOS version 1 on 2007-06-29