Input

Decoded Output

What Is the JSFuck Decoder?

This JSFuck Decoder helps analyze JavaScript encoded using JSFuck patterns and beautifies JavaScript. Paste obfuscated or minified code; get readable output for debugging and analysis. The ECMAScript spec defines the language.

This tool runs entirely in your browser. Nothing is sent to a server. For obfuscating code, use JavaScript Obfuscator. For formatting only, use JavaScript Formatter. For validation, use JavaScript Validator.

How to Decode JSFuck

1

Paste or Upload

Paste JSFuck or mixed obfuscated JavaScript into the editor. The tool applies decoding and formatting for easier inspection.

2

View Decoded Output

The output shows best-effort decoding and normalization. Extremely nested payloads may still need manual analysis.

3

Copy or Download

Use Copy or Download to get the result. For running code, use JavaScript Console.

JSFuck Decoder Example

Here is an example of decoding JSFuck-style symbols and escapes.

Example: Symbol-heavy obfuscated expression

JSFuck input:

Input

Decoded output:

Output

When the JSFuck Decoder Helps

This is useful for malware triage, CTF challenges, and reverse-engineering scripts that use JSFuck notation. Decode first, then inspect behavior in a safer workflow.

Frequently Asked Questions

Is my data private?

Yes. Decoding runs entirely in your browser. No data is sent to any server.

Does this decode every JSFuck payload?

It handles many symbol-heavy patterns, but deeply layered payloads can still require manual deconstruction.

Can it fully reverse obfuscation?

It depends on the obfuscation. Simple patterns are reversed. Heavy obfuscation may leave some code hard to read.

JSFuck Decoder vs Deobfuscator?

JSFuck Decoder targets symbol-based encodings. The general deobfuscator is better for mixed or non-JSFuck obfuscation.

Is it legal to deobfuscate?

Use for debugging your own code, security research, or with permission. Check licenses and terms for third-party code.

Related Tools

ECMAScript. MDN JavaScript. Terser. Chrome DevTools. Babel.