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JavaScript formatter & minifier

Beautify or minify JavaScript code instantly. Strips comments, normalizes indentation, compresses whitespace for production.

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What is JavaScript Formatter & Minifier?

A JavaScript formatter and minifier is an essential developer tool that transforms your JavaScript code between two states: readable (beautified) and compressed (minified). When you beautify JavaScript, the tool adds proper indentation, line breaks, and consistent spacing so the code is easy to read, debug, and maintain. When you minify JavaScript, it strips all comments, collapses whitespace, and compresses operator spacing to produce the smallest possible file size. Smaller JavaScript files load faster, reducing page load times and improving Core Web Vitals scores like Largest Contentful Paint (LCP) and Total Blocking Time (TBT). This free online JavaScript formatter runs entirely in your browser — no code is uploaded to any server, making it safe for proprietary codebases. Whether you are cleaning up minified third-party scripts or preparing your own code for production deployment, this tool handles both directions instantly.

How to Use JavaScript Formatter & Minifier

  1. 1

    Paste your JavaScript code

    Copy your JavaScript source code and paste it into the input textarea. The tool accepts any valid JS including ES6+, arrow functions, template literals, and more.

  2. 2

    Choose format or minify mode

    Click "Format" to beautify the code with proper indentation (choose 2 or 4 spaces), or click "Minify" to compress it by stripping comments and collapsing whitespace.

  3. 3

    Copy the result

    Click the Copy button to copy the formatted or minified output to your clipboard. For minified code, you will see the size savings percentage displayed above the output.

Features

  • Beautify JavaScript with 2-space or 4-space indentation
  • Minify JS by removing comments and compressing whitespace
  • Real-time size savings calculator showing bytes and percentage saved
  • Handles ES6+ syntax including arrow functions and template literals
  • Runs 100% client-side — your code never leaves the browser
  • One-click copy to clipboard with visual confirmation

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Frequently Asked Questions

Is my JavaScript code sent to a server?+
No. This tool runs entirely in your browser using client-side JavaScript. Your code never leaves your machine, making it safe for proprietary or sensitive codebases.
What is the difference between formatting and minifying JavaScript?+
Formatting (beautifying) adds proper indentation, line breaks, and spacing to make code readable and maintainable. Minifying does the opposite — it strips comments, removes unnecessary whitespace, and compresses the code to reduce file size for production deployment.
How much file size reduction can I expect from minification?+
Typical JavaScript minification reduces file size by 30-60% depending on how many comments and how much whitespace the original code contains. Heavily commented code with verbose formatting will see the largest reductions.
Does the formatter handle ES6+ and modern JavaScript syntax?+
Yes. The formatter handles arrow functions, template literals, destructuring, spread operators, async/await, and other modern JavaScript syntax. It processes the code structurally based on braces and semicolons.
Can I use this tool to format minified third-party libraries?+
Yes. Paste any minified JavaScript and switch to Format mode. The tool will add proper line breaks at braces and semicolons with your chosen indentation level, making the code readable for debugging.
Does minification affect how my JavaScript code runs?+
No. Minification only removes comments and unnecessary whitespace — it does not change the logic or behavior of your code. The minified output is functionally identical to the original source.