JavaScript Formatter & Beautifier Online Free

JavaScript Formatter — beautify and indent JavaScript error runs in your browser · nothing uploaded

Indent

⌃⏎ run · ⎋ clear · / focus input

JAVASCRIPT ⇅ upload

⇅ drop a file to load it

FORMATTED

send output to

no matches

Handles pastes up to ~5MB smoothly in your browser — bigger files still work, just budget a second or two.

JavaScript Formatter Online

Updated 2026-07-09

Format and beautify JavaScript online for free. Paste minified or inconsistently indented JS and SnapTools rewrites it with consistent indentation, spacing, and line breaks — ready to copy or download. Everything runs in your browser, so your code is never uploaded.

Minified or bundled JavaScript is a wall of text that is almost impossible to read. Beautifying restores structure without changing a single statement, so you can inspect third-party scripts, review an unfamiliar file, or tidy a snippet before committing — with the behaviour left untouched.

// how to use

1 Paste minified or messy JavaScript into the input panel on the left.
2 SnapTools re-indents it with consistent spacing and line breaks as you type.
3 Choose your indent size, then copy or download the beautified code.

// examples

Minified JS to readable

Input

function add(a,b){return a+b}const x=add(1,2);

Output

function add(a, b) {
    return a + b;
}
const x = add(1, 2);

Compressed object

Input

const u={name:"Ada",roles:["admin","dev"]};

Output

const u = {
    name: 'Ada',
    roles: ['admin', 'dev'],
};

// common uses

Making minified or bundled JavaScript readable for inspection Standardising indentation before committing code Reviewing an unfamiliar script's structure Cleaning up snippets pasted from the web

// faq

No. Beautifying runs entirely in your browser, so your JavaScript never leaves your machine.

No. Only whitespace, indentation, and line breaks change — statements, identifiers, and logic are preserved, so the code behaves exactly the same.

Yes. It re-expands minified or single-line JavaScript into readable, indented code, which makes bundled or third-party scripts far easier to inspect.

It handles standard JavaScript including arrow functions, template literals, classes, and object shorthand. Framework-specific syntax like JSX is not its target.

Match your project's style — four spaces, two spaces, or tabs. The default keeps output readable for most codebases.

// related

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Use this via API

Get a free API key →

curl -X POST https://snaptools.dev/api/v1/tools/js-formatter \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"code":"function add(a,b){return a+b}const x=add(1,2);"}'