Here are some of the best JavaScript compressors available −
Google Closure Compiler
The Google Closure compiler runs JavaScript quickly and used for a superior JavaScript. It parses your JavaScript, analyzes it, removes dead code, rewrites, and minimizes what's left.
JSMin
If you want to minify, then use the JSMin to remove unnecessary comments.
YUI Compressor
The YUI Compressor is used to minify the JavaScript files fastly and is secure.