JavaScript Minifier & Beautifier

Minify or beautify JavaScript. Shorten variable names, remove whitespace, and show compression savings.

Free Always No Account Needed 100% Client-Side

Input JavaScript (273 bytes)

Output (293 bytes)

function calculateTotal(items) {
  return items.reduce(function(acc, item) {
    if (item.quantity > 0) {
      return acc + (item.price * item.quantity);
    } return acc;
  }, 0);
} const applyDiscount = (total, discount) => {
  return discount > 0 ? total * (1 - discount / 100) : total;
};

How to use JavaScript Minifier & Beautifier Online

1
Input Data or ParametersPaste your input string, code payload, or select parameters into the editor.
2
Instant Local ComputationThe tool processes your request in real-time inside your browser using client-side JavaScript.
3
Copy or Export OutputCopy the formatted result to your clipboard or download the output payload instantly.

About this tool

JavaScript is often the largest contributor to page weight. Minification significantly reduces download and parse time.

JS Minifier compresses JavaScript by: - Removing whitespace, comments, and newlines - Shortening variable and function names (mangling) - Simplifying boolean expressions (!!0 → false) - Removing dead code branches

JS Beautifier reformats minified or compressed JavaScript with proper indentation, consistent spacing, and newlines — turning production code back into readable source (note: mangled variable names cannot be recovered without a source map).

This tool uses a pure JavaScript implementation for client-side processing. No code is ever sent to a server.

Frequently Asked Questions

What is the difference between minification and obfuscation?

Minification removes whitespace/comments for size. Obfuscation deliberately makes code hard to read (renamed variables, encoded strings). This tool only minifies.

Can I un-minify (beautify) production code?

You can re-add whitespace and indentation, but if variable names were mangled you can't recover the original names without a source map.

Does minification break my code?

Standard whitespace and comment removal is always safe. Name mangling can occasionally break code that uses eval() or dynamic property access.

Should I minify ES modules?

Yes, but use a bundler like Vite or esbuild for production — they handle imports, tree-shaking, and minification together.

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