Toolsly
Minifier

JavaScript Minifier

Paste any JavaScript or ES module and get a compressed, single-line version powered by Terser. Compression eliminates dead code and shortens expressions; mangling renames local identifiers to single letters for maximum size reduction. You can turn mangling off if you need stack traces with readable names. Runs entirely in your browser — your source never leaves this page.

Privacy

Runs entirely in your browser — nothing is sent to any server.

Cost

Free. No sign-up, no watermark.

Type

Minifier

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Frequently asked

Is JavaScript Minifier free to use?

Yes. JavaScript Minifier is completely free with no sign-up, no watermark, and no usage limits. Toolsly does not charge for any of its tools.

Do my files and data stay private?

Yes — JavaScript Minifier runs entirely in your browser using your device's CPU. Files and text are never uploaded to our servers, so your data stays private.

How does JavaScript Minifier work?

Open JavaScript Minifier, paste or fill in the input fields, and the result updates instantly. Everything runs in your browser — no upload, no waiting.

Which browsers does JavaScript Minifier support?

Any modern browser works — Chrome, Firefox, Safari, and Edge on desktop and mobile. JavaScript Minifier uses standard web APIs and does not require any plugin, extension, or sign-up.