Is my JavaScript code safe? Does it get sent anywhere?

Yes, it is completely safe. All processing happens directly in your browser using JavaScript. Your code is never sent to any server, stored in a database, or logged anywhere. It stays on your device the entire time.

What does the JavaScript Minifier actually do?

The minifier removes single-line comments (// ...) and block comments (/* ... */), collapses multiple spaces and blank lines, and optionally joins all lines into a single line. This reduces file size without changing the runtime behaviour of your code.

Will minifying JavaScript break my code?

Whitespace removal and comment stripping never break valid JavaScript. The 'join lines' option is safe for most code too, because JavaScript's automatic semicolon insertion (ASI) rules are well-defined. If you have unusual ASI-sensitive patterns, test the output before deploying.

How much can I reduce my JavaScript file size?

Comment and whitespace removal typically reduces size by 20–50% for developer-formatted code. Libraries with heavy comments (like jQuery source) can shrink by 60% or more. For the maximum reduction, use a full tree-shaker like esbuild or webpack in your build pipeline.

Does this tool support ES6+ syntax like arrow functions and classes?

Yes. The minifier is syntax-aware and correctly handles template literals, arrow functions, destructuring, classes, and all modern JavaScript syntax without accidentally modifying string or regex content.

What is the difference between this and tools like UglifyJS or Terser?

Tools like UglifyJS and Terser perform deep optimisation: dead code elimination, constant folding, and variable name mangling. This tool focuses on the safe, fast operations — comment removal and whitespace compression — that require no AST parsing and work instantly in the browser.

100% Client-Side · No Uploads

Minify JavaScript
Instantly in Your Browser

Paste your JS, remove comments, compress whitespace, and see exactly how much you save — all without sending a single byte to any server.

🔒

Totally Private

Your code never leaves the browser. Zero uploads, zero tracking, zero risk.

⚡

Instant Results

Minification happens in real time as you type — no button press needed.

📉

Size Stats

See original vs. minified byte count and exact compression percentage.

Frequently Asked Questions

Everything you need to know about JavaScript Minifier.