What? What is Javascript deobfuscation? JS deobfuscation is the opposite of obfuscation . The goal is to rewrite/decode/deobfuscate/decrypt/uncompress the obfuscated javascript code to recover native JS. The tools are called unofuscator or deofuscator.
There are several different types of deobfuscators. Some are specific to a programming language and others are general purpose. A general purpose deobfuscator is the most flexible but can be cumbersome to use. You must know what is doing before deciding what to do. type of deobfuscator to use.
Note: Don't think that simply pasting the obfuscated code into this online tool will deobfuscate it, it's quite difficult to find a tool that has what it takes to deobfuscate a JavaScript file right away, You have to be patient until you find the right one for your purposes, etc...