JavaScript Formatter

Clean up messy or minified JavaScript in one click. Prettier reformats your code with consistent style, Terser compresses it for production, and both run locally so your source never leaves the page.

Input

Tip: press Ctrl/⌘ + Enter to format.

Formatting runs with Prettier and Terser loaded straight into your browser — your code is never uploaded.
All processing is done locally in your browser. Your images never leave your device.

How to use

  1. 1

    Paste your JavaScript into the editor.

  2. 2

    Press Format to beautify or Minify to compress.

  3. 3

    Compare the original and output sizes.

  4. 4

    Copy the result or download it as a .js file.

Supported formats

Accepts

Produces

FAQ

Prettier's standalone browser build, so the output matches what Prettier produces in your editor.

No. Prettier and Terser are loaded into your browser and run entirely on your device.

Yes, including ES2022 features, optional chaining, class fields and JSX.

Terser is a safe, widely used minifier, but always test minified output before shipping it.

The formatter libraries are loaded only when you press the button, which keeps the rest of the site fast.

About this tool: JavaScript Formatter

Consistent JavaScript, minified or expanded

The JavaScript Formatter beautifies or minifies JS code. Beautify mode re-indents dense one-liners into readable structure; minify mode strips comments and whitespace — and applies real dead-code elimination and mangling via Terser, the same engine used by production build tools.

Readable code is debuggable code: pasting a compressed snippet from a bundle and beautifying it turns gibberish into step-through logic. Conversely, shipping readable code wastes bytes — minification routinely cuts 30–50% from source size, which adds up across an entire application.

Formatting runs locally; your source — and any embedded secrets during testing — stays on your machine. Choose your indent style, verify minified output still parses correctly, and copy results straight into your editor or deployment.

Like every Piclizer tool, this one runs entirely in your browser — your files stay on your device.

Related tools