How can I target only Internet Explorer 11 with JavaScript?

Question

What's the least error-prone way to target just IE11 with JavaScript?

Note: This should really only be done for analytics or informing the user what browser they're using. For everything else, there's feature detection.

Answer 1

The User-agent string for IE 11 is currently this one :

Mozilla/5.0 (Windows NT 6.3; Trident/7.0; rv 11.0) like Gecko

Windows 10 example:

Mozilla/5.0 (Windows NT 10.0; Trident/7.0; rv:11.0) like Gecko

Which means your can simply test, for versions 11.xx,

var isIE11 = /Trident.*rv[ :]*11./.test(navigator.userAgent);

As IE10 user agent was

Mozilla/5.0 (compatible; MSIE 10.0; Windows NT 6.2; Trident/6.0)

it's probably also safe to bet on the fact that now Trident/X is supposed to be the real versionning.