Find and Show jQuery Version
You can use $().jquery , jQuery.fn.jquery and $()['jquery'] to find the jQuery version.
example
If you want to know jQuery UI library version, you can use $.ui.version
example
example

Full Source
jQuery Version History
Version 1.0 was the first stable release of jQuery. Versions 2.0 dropped support for Internet Explorer 6-8 to increase jQuery's overall performance and reduce the library's file size. With the release of version 3.0 both versions 1.11.1 and 2.1.1 will be upgraded to jQuery Compat 3.0 and jQuery 3.0. With the release of Version 3.0 there's no reason to stick to either version 1.0 or 2.0. You can check the full details of... jQuery release history , and also you can check jQuery Core... All Versions .