How to unobfuscate java-script code

Question

How to un obfuscate java-script code like that : it takes alot of time to know the expression obfuscate for the javascript to protect the code , but I'm tring to get the main code of this script but don't know How ?

var _0x843d=["\x75\x73\x65\x20\x73\x74\x72\x69\x63\x74","\x53\x4C\x41\x4D\x52","\x6E\x61\x76","\x72\x65\x73\x69\x7A\x65","\x77\x69\x64\x74\x68","\x74\x6F\x70\x2D\x6E\x61\x76\x2D\x63\x6F\x6C\x6C\x61\x70\x73\x65","\x68\x61\x73\x43\x6C\x61\x73\x73","\x2E\x6E\x61\x76\x62\x61\x72\x2D\x66\x69\x78\x65\x64\x2D\x74\x6F\x70","\x61\x64\x64\x43\x6C\x61\x73\x73","\x72\x65\x6D\x6F\x76\x65\x43\x6C\x61\x73\x73","\x74\x6F\x70","\x6F\x66\x66\x73\x65\x74","\x2E\x6E\x61\x76\x62\x61\x72","\x73\x63\x72\x6F\x6C\x6C","\x64\x72\x6F\x70\x64\x6F\x77\x6E","\x61\x63\x74\x69\x76\x65\x2D\x73\x75\x62","\x65\x61\x73\x65\x4F\x75\x74\x45\x78\x70\x6F","\x3A\x6E\x6F\x74\x28\x2E\x65\x78\x29","\x6F\x6E\x65\x50\x61\x67\x65\x4E\x61\x76","\x2E\x6E\x61\x76\x62\x61\x72\x2D\x6E\x61\x76\x20\x2E\x64\x72\x6F\x70\x64\x6F\x77\x6E","\x61\x63\x74\x69\x76\x65","\x2E\x6E\x61\x76\x62\x61\x72\x2D\x6E\x61\x76","\x73\x6C\x69\x64\x65\x44\x6F\x77\x6E\x48\x65\x61\x64","\x2D\x35\x30\x30\x70\x78","\x30","\x63\x73\x73","\x2E\x70\x61\x67\x65\x48\x65\x61\x64","\x2E\x70\x61\x67\x65\x48\x65\x61\x64\x20\x2E\x68\x65\x72\x6F\x20\x68\x31\x2C\x20\x2E\x70\x61\x67\x65\x48\x65\x61\x64\x20\x2E\x68\x65\x72\x6F\x20\x68\x33","\x72\x65\x61\x64\x79","\x30\x70\x78","\x31","\x65\x61\x73\x65\x4F\x75\x74\x43\x75\x62\x69\x63","\x61\x6E\x69\x6D\x61\x74\x65","\x2E\x70\x61\x67\x65\x48\x65\x61\x64\x20\x2E\x68\x65\x72\x6F\x20\x68\x33","\x2E\x70\x61\x67\x65\x48\x65\x61\x64\x20\x2E\x68\x65\x72\x6F\x20\x68\x31","\x64\x65\x6C\x61\x79","\x73\x74\x6F\x70","\x6C\x6F\x61\x64","\x70\x61\x72\x61\x6C\x6C\x61\x78","\x74\x6F\x75\x63\x68","\x73\x65\x74","\x72\x61\x6E\x64\x6F\x6D","\x69\x6E\x69\x74","\x70\x72\x65\x6C\x6F\x61\x64\x65\x72","\x6F\x76\x65\x72\x66\x6C\x6F\x77","\x76\x69\x73\x69\x62\x6C\x65","\x62\x6F\x64\x79","\x66\x61\x64\x65\x4F\x75\x74","\x23\x70\x72\x65\x6C\x6F\x61\x64\x65\x72","\x73\x6C\x69\x64\x65\x72","\x73\x75\x70\x65\x72\x73\x6C\x69\x64\x65\x73","\x6F\x77\x6C\x43\x61\x72\x6F\x75\x73\x65\x6C","\x65\x61\x63\x68","\x73\x6B\x69\x6C\x6C\x62\x61\x72","\x61\x6E\x69\x6D\x61\x74\x65\x64","\x75\x73\x65\x72\x41\x67\x65\x6E\x74","\x74\x65\x73\x74","\x64\x61\x74\x61\x2D\x70\x65\x72\x63\x65\x6E\x74","\x61\x74\x74\x72","\x2E\x73\x6B\x69\x6C\x6C\x62\x61\x72\x2D\x62\x61\x72","\x66\x69\x6E\x64","\x68\x65\x69\x67\x68\x74","\x6F\x75\x74\x65\x72\x48\x65\x69\x67\x68\x74","\x77\x61\x79\x70\x6F\x69\x6E\x74","\x2E\x73\x6B\x69\x6C\x6C\x62\x61\x72","\x76\x69\x64\x65\x6F\x42\x67\x59\x54","\x74\x75\x62\x75\x6C\x61\x72","\x3C\x69\x6D\x67\x20\x73\x72\x63\x3D\x27\x69\x6D\x67\x2F\x62\x67\x2D\x68\x65\x61\x64\x2D\x31\x2E\x6A\x70\x67\x27\x20\x61\x6C\x74\x3D\x27\x27\x20\x2F\x3E","\x68\x74\x6D\x6C","\x62\x6F\x6F\x74\x73\x74\x72\x61\x70\x43\x61\x72\x6F\x75\x73\x65\x6C","\x63\x61\x72\x6F\x75\x73\x65\x6C","\x66\x69\x74\x56\x69\x64\x73","\x70\x6F\x72\x74\x66\x6F\x6C\x69\x6F\x46\x69\x6C\x74\x65\x72","\x70\x72\x65\x76\x65\x6E\x74\x44\x65\x66\x61\x75\x6C\x74","\x63\x75\x72\x72\x65\x6E\x74","\x64\x61\x74\x61\x2D\x67\x72\x6F\x75\x70","\x61\x6C\x6C","\x69\x6E\x61\x63\x74\x69\x76\x65","\x2E\x70\x6F\x72\x74\x66\x6F\x6C\x69\x6F\x2D\x6C\x69\x6E\x6B","\x75\x6E\x64\x65\x66\x69\x6E\x65\x64","\x2C","\x73\x70\x6C\x69\x74","\x63\x6C\x69\x63\x6B","\x68\x6F\x76\x65\x72","\x70\x6F\x72\x74\x66\x6F\x6C\x69\x6F","\x70\x6F\x72\x74\x66\x6F\x6C\x69\x6F\x45\x78\x70\x61\x6E\x64\x65\x72","\x73\x63\x72\x6F\x6C\x6C\x41\x6E\x69\x6D","\x79\x65\x73","\x64\x65\x66\x61\x75\x6C\x74\x73","\x66\x6E","\x61\x6E\x69\x6D\x61\x74\x69\x6F\x6E","\x64\x61\x74\x61","\x64\x61\x74\x61\x2D\x61\x6E\x69\x6D\x61\x74\x69\x6F\x6E","\x64\x61\x74\x61\x2D\x61\x6E\x69\x6D\x61\x74\x69\x6F\x6E\x2D\x64\x65\x6C\x61\x79","\x61\x6E\x69\x6D\x61\x74\x69\x6F\x6E\x2D\x64\x65\x6C\x61\x79","\x20\x76\x69\x73\x69\x62\x6C\x65","\x25","\x2E\x61\x6E\x69\x6D\x61\x74\x65\x64","\x76\x69\x73\x69\x62\x69\x6C\x69\x74\x79","\x66\x69\x78\x65\x64","\x2E\x62\x61\x63\x6B\x67\x72\x6F\x75\x6E\x64\x2D\x6D\x69\x64\x64\x6C\x65\x2D\x66\x75\x6C\x6C","\x6D\x61\x67\x6E\x69\x66\x69\x63","\x6D\x61\x67\x6E\x69\x66\x69\x63\x50\x6F\x70\x75\x70","\x63\x6F\x6E\x74\x61\x63\x74\x46\x6F\x72\x6D","\x63\x6C\x69\x63\x6B\x20\x74\x6F\x75\x63\x68\x73\x74\x61\x72\x74","\x64\x69\x73\x61\x62\x6C\x65\x64","\x70\x72\x6F\x70","\x3C\x69\x20\x63\x6C\x61\x73\x73\x3D\x27\x66\x61\x20\x66\x61\x2D\x63\x6F\x67\x20\x66\x61\x2D\x73\x70\x69\x6E\x27\x3E\x3C\x2F\x69\x3E\x20\x53\x45\x4E\x44\x49\x4E\x47","\x23\x63\x6F\x6E\x74\x61\x63\x74\x2D\x73\x75\x62\x6D\x69\x74","\x23\x63\x6F\x6E\x74\x61\x63\x74\x2D\x66\x6F\x72\x6D","\x73\x65\x72\x69\x61\x6C\x69\x7A\x65","\x50\x4F\x53\x54","\x69\x6E\x63\x2F\x63\x6F\x6E\x74\x61\x63\x74\x2E\x70\x68\x70","\x6A\x73\x6F\x6E","\x73\x74\x61\x74\x75\x73","","\x76\x61\x6C","\x23\x63\x6F\x6E\x74\x61\x63\x74\x2D\x66\x6F\x72\x6D\x20\x69\x6E\x70\x75\x74","\x23\x63\x6F\x6E\x74\x61\x63\x74\x2D\x66\x6F\x72\x6D\x20\x74\x65\x78\x74\x61\x72\x65\x61","\x65\x6D\x70\x74\x79","\x23\x63\x6F\x6E\x74\x61\x63\x74\x2D\x66\x6F\x72\x6D\x2D\x72\x65\x73\x70\x6F\x6E\x73\x65","\x3C\x69\x20\x63\x6C\x61\x73\x73\x3D\x27\x66\x61\x20\x66\x61\x2D\x63\x68\x65\x63\x6B\x27\x3E\x3C\x2F\x69\x3E\x20\x53\x55\x42\x4D\x49\x54","\x61\x6A\x61\x78","\x6F\x6E"];

I have another question related to that , Could I use this script as it's or I have to decode it to use at my HTML5 page ?

Answer 1

The point of obfuscation is to make it very challenging to restore the original code as written while maintaining the same functionality. So to answer your first question there really is no way to get back to the original code as the author clearly didn't want you to see it or be able to edit it. To answer your second question yes you should be able to use it normally assuming it was properly obfuscated.

I suggest you do a little reading on the topic: http://en.wikipedia.org/wiki/Obfuscation_%28software%29

There might be a few deobfuscation tools out there for javascript, but the chance that these work well is probably low.