This feature is no longer recommended. Though some browsers might still support it, it may have already been removed from the relevant web standards, may be in the process of being dropped, or may only be kept for compatibility purposes. Avoid using it, and update existing code if possible; see the compatibility table at the bottom of this page to guide your decision. Be aware that this feature may cease to work at any time.
Returns either "
4.0" or a string representing version information about
Do not rely on this property to return the correct browser version.
4.0" or a string representing version information about the
alert('Your browser version is reported as ' + navigator.appVersion);
window.navigator.userAgent property may also contain the version
number (for example
Mozilla/5.0 (Windows; U; Win98; en-US; rv:0.9.2) Gecko/20010725 Netscape 6/6.1"),
but you should be aware of how easy it is to change the user agent string and "spoof"
other browsers, platforms, or user agents, and also how cavalier the browser vendor
themselves are with these properties.
window.navigator.userAgent properties have been used in "browser sniffing"
code: scripts that attempt to find out what kind of browser you are using and adjust
pages accordingly. This lead to the current situation, where browsers had to return fake
values from these properties in order not to be locked out of some websites.
|HTML Standard (HTML)|
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