(online or offline) – you can download its repo and run index.html locally without internet. JS Nice web version if you need renaming & beautifying.
Better – use a bookmarklet: javascript:(function()document.body.innerText=eval(prompt("Packed code?")))(); (Only for trusted code) javascript+deobfuscator+and+unpacker+portable
Standalone .exe or script files that run from a USB drive without touching the system registry. (online or offline) – you can download its