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JS Minifier

Compress JavaScript by removing whitespace and comments, shortening variable names, and applying optimisations to reduce file size.

All processing is done locally in your browser. No data is sent to our servers.

How JavaScript Minification Works

This minifier uses Terser, a production-grade JavaScript parser and compressor. It removes all whitespace, comments, and unnecessary characters. It also applies optimisations like dead code elimination, constant folding, and variable mangling to produce the smallest possible output.

The output is functionally identical to the input - it will execute with exactly the same behaviour but typically 40-60% smaller in file size.

Minification Techniques

Whitespace Removal

Strips all unnecessary spaces, tabs, newlines, and comments from the code.

Variable Mangling

Shortens local variable and function names to single or two-character identifiers.

Dead Code Elimination

Removes unreachable code, unused variables, and redundant statements.

Why Minify JavaScript

Faster Page Loads

Smaller files download faster and parse quicker, improving Time to Interactive and overall page performance.

Reduced Bandwidth

Minified scripts consume less bandwidth, saving costs for high-traffic websites and mobile users on limited data plans.

Production Deployment

Minification is a standard step in production build pipelines alongside bundling and tree-shaking.

Source Map Compatible

Minified code can be paired with source maps for debugging production issues in developer tools.