Detect Windows Version With JavaScript

Specifically, I am trying to detect Windows XP users as they are not compatible with my software.

Is there a way to detect with at l开发者_StackOverflow社区east 70% or higher accuracy?

Try navigator.appVersion

http://msdn.microsoft.com/en-us/library/ms533080(v=VS.85).aspx
https://developer.mozilla.org/en/DOM/window.navigator.appVersion

I have Windows 7 here and the navigator.appVersion returns a string containing "NT 6.1" in these browsers: Chrome, Opera, Safari, IE9 beta.

Only Firefox does not return that info in that string :(

btw, WinXP is "NT 5.1", Vista is "NT 6.0" ...

Update

navigator.userAgent returns the "NT version" string in all 5 browsers. That means that userAgent is the property that is able to tell the Windows version.

It appears that you can use the navigator host object:

var os = navigator.platform

See here for more info: http://www.jguru.com/faq/view.jsp?EID=1100686

Also: http://www.quirksmode.org/js/detect.html

window.navigator.appVersion.split("NT")[1].split(";")[0].trim()

Will return the Windows version.