JavaScript Obfuscator & Deobfuscator
Obfuscate JavaScript to protect your source code, or deobfuscate to reverse-engineer minified/obfuscated scripts. Supports variable renaming, string encoding, dead code injection, and expression simplification. Everything runs in your browser — your code stays private.
What Is JavaScript Obfuscation?
JavaScript obfuscation transforms your readable source code into a functionally equivalent but extremely difficult-to-read version. Unlike minification, which simply removes whitespace and comments, obfuscation deliberately mangles variable names, encodes strings, injects fake code, and restructures control flow to deter reverse engineering.
Because JavaScript runs on the client side, anyone can view your code with browser DevTools. Obfuscation raises the barrier significantly, protecting proprietary algorithms, license checks, API keys, and business logic from casual inspection.
Obfuscation Techniques Explained
- Variable Renaming — replaces meaningful names like
userNamewith cryptic identifiers like_0x4a2f - String Encoding — converts readable strings to hex (
\x48\x65\x6c\x6c\x6f) or Unicode (\u0048\u0065\u006c\u006c\u006f) escapes - Dead Code Injection — inserts fake if-blocks and unused variables that never execute but clutter analysis
- Control Flow Flattening — replaces normal if/else/loop structures with switch-case state machines, making logic extremely hard to follow
- Number-to-Expression — converts numeric literals like
42to expressions like(0x1f + 0xb)
When to Obfuscate vs. When to Deobfuscate
Obfuscate when shipping client-side JavaScript that contains proprietary algorithms, license validation, anti-cheat logic, or any business-critical code you want to protect from casual theft or tampering.
Deobfuscate when analyzing third-party scripts for security auditing, debugging production issues, understanding malware behavior, or learning how a particular library works under the hood.
Obfuscation vs. Minification
Minification reduces file size by stripping whitespace and comments. Obfuscation increases file size but makes the code incomprehensible. In production, you typically minify first for performance, then obfuscate the critical portions. Our JavaScript Minifier handles the size-reduction step.