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JavaScript Minifier

Minify JavaScript with the real Terser engine.Developer Tools

JavaScript Minifier

Minify JavaScript with the real Terser engine (loaded on demand, ~350 KB only when this page runs it): mangle names, compress and strip comments.

About this tool

Terser — the minifier behind most production bundlers — runs on demand in your browser: compression, name mangling and comment removal with a real parser, so code semantics survive.

How to use the JavaScript Minifier tool

  1. Paste your JavaScript. ES5 or modern syntax.
  2. Minify. Terser loads on demand and runs locally.
  3. Copy the output. Minified, semantics-preserving code.

Supported formats

Input

  • Plain text or file input

Output

  • Converted or analysed output

Inputs are validated before anything is processed. Invalid values and unsupported files are rejected with a clear error instead of failing silently.

Frequently asked questions

Why is the first run slower?

Terser downloads on demand and is cached afterwards; it never loads on other pages.

Is my code uploaded?

No — minification runs in the tab.

Does it handle modules?

Scripts are treated as classic scripts; use a bundler for import and export code.

Privacy

Everything you enter stays in this browser tab. There is no upload endpoint for tool inputs, no account, and no server-side copy of your text or files. Results are produced locally and disappear when you close the page.

No account is required and no file is ever uploaded. See the privacy policy for details about analytics and the limited data this site stores.

Known limitations

  • No sourcemap generation in this release.

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