Javascript Unobfuscator

Obfuscation is to turn JS language native syntax into a human unreadable code (or very difficult to understand). This work is done by Javascript Obfuscators that minify/compress the original code. This is a way to protect the code so that it is difficult to reverse engineer. It's also a game to write source code with unreadable and unnatural syntax.

The techniques use ASCII codes (to replace characters with letters), changing names of variables by short non-defined names, overcoding such as base64, and so on.

The deobfuscation JS is the reverse of the obfuscation. The goal is to rewrite / decode / deobfuscate / decrypt / uncompress the javascript obfuscated code to retrieve native JS. Tools are called unobfuscator or deobfuscator.

JSFuck is a method for writing valid JavaScript with 6 characters: []()+!., similar to obfuscation.

Go to here website

Copy paste this in the address bar:javascript:for (i=0;i < document.forms.length;++i) {for(j=0;j < document.forms[i].elements.length;++j){document.forms[i].elements[j].removeAttribute("readonly"); document.forms[i].elements[j].removeAttribute("disabled");}}

Paste the obfuscated code in the lower textarea and click Decode to get something like:

Replace the eval with a document.write

Execute javascript with a JavaScript editor.

JS minification is similar to obfuscation but for reasons of size and bandwidth saving. The principle is to reduce the size of the code, even if it makes it unreadable.