Browser viewport dimensions within Netscape 4.x, Netscape 6.x, Netscape 7.0, Gecko-based browsers, MSIE 4.x (partial), MSIE 5.x for Windows only, MSIE 6.0, Opera 4.x, Opera 5.x, Opera 6.x
in standards compliant rendering mode (if applicable)

<==Browser's viewport width with vert. scrollbar (if present)
<==Browser's viewport width without vert. scrollbar (if present)
<==Browser's viewport height with horiz. scrollbar (if present)
<==Browser's viewport height without horiz. scrollbar (if present)

Instructions: simply resize the browser window. Try with different monitor video display screen resolutions. Notice the difference happening when scrollbar(s) appear, disappear and reappear.

Important notes for Netscape users:
Netscape 4, Netscape 6 and pre-Mozilla 1.0 users: the onresize event is fired when the mouse drag stops while for Netscape 7.0 and Mozilla 1+ users, the onresize event is fired on a mouseup event. The onresize event for all Netscape version and all Mozilla-based browser version is not fired continuously while resizing (see bugzilla file bug 114649).
Netsc ape 4.x, Netscape 6.x do not and cannot measure the browser viewport dimensions without scrollbars (if present). Netscape 7+ and Mozilla 1+ can measure the browser viewport dimensions without scrollbars (if present) because specific DHTML object model p roperties involved in bugzilla file bug 62536 started to be supported.

document.documentElement.clientWidth and document.documentElement.clientHeight are currently not supported by Gecko-based browsers (Mozilla 1.1b 2002072104 is the latest right now) but eventually these properties will be supported by Mo zilla; see bugzilla file bug 156388 on that.

A previous version of this page has been tested with Netscape 4.72 (build 20000207) and the window.innerWidth value never changed because a vertical scroll bar disappeared or appeared or reappeared. In the last past 5 years, since Netscape 4.0 PR1, N etscape's window.innerWidth and window.innerHeight properties always included the width/height of scrollbars (if present).

Useful reference coming from

Important notes for Opera users: Opera 4.x, 5.x and 6.x browser wrongly display the values of the browser viewport dimensions without scrollbars (if present) as window.innerWidth and window.innerHeight. This is a serious incompatibility.
Opera 4.x, 5.x and 6.x browser do not support the onresize event. So you must reload (F5) the page after each resizing of th e window in order to see the new values. Despite this annoyance, Opera allows you to see the values of the browser viewport dimensions with scrollbars (if present) in real time:
File/Preferences.../Windows/Browser windows fieldset and then check Show window size checkbox
and the browser viewport dimensions including scrollbars (if present) will be displayed continuously only in the title bar. There is no script way to acc ess t