JavaScript Minifier

Minify and compress JavaScript code by removing comments, whitespace and unnecessary characters. Reduce file size, improve load times and optimize your site’s performance.

⚡ Client-side processing only 🧮 Shows size & savings 🔒 No code is uploaded
Original JavaScript Paste your formatted or unformatted JS code here
Minified JavaScript Result after minification (compact output)
Original Size
0 B
0 lines
Minified Size
0 B
0 lines
Saved
0 B
0% compression

Free Online JavaScript Minifier & Compressor

The JavaScript Minifier from PowerSEOTools.online helps you compress and optimize your JS files with a single click. By removing comments, line breaks, extra spaces and unnecessary characters, you can significantly reduce file size and improve loading speed.

Minified JavaScript is perfect for production builds, CDNs and performance-focused deployments where bandwidth and speed matter more than human readability.

Why Minify JavaScript?

Every extra byte of JavaScript must be downloaded, parsed and executed by the browser. Minification reduces the amount of data without changing the logic of your code.

  • Faster page loads: Smaller JS files download and execute faster, especially on mobile networks.
  • Improved Core Web Vitals: Lean assets help with metrics like FID and INP.
  • Bandwidth savings: Less data transfer for both you and your users.
  • Production-ready assets: Keep readable JS during development and ship minified JS to production.

What This JavaScript Minifier Does

  • Removes comments: Strips out // line comments and /* block comments */ while preserving strings.
  • Collapses whitespace: Reduces sequences of spaces, tabs and newlines into compact spacing where safe.
  • Trims around punctuation: Removes unnecessary spaces around common punctuation such as braces, parentheses and semicolons.
  • Keeps strings & regex intact: Preserves code inside quotes and most regular expression literals.
  • Shows savings: Displays original size, minified size, and total bytes saved with an estimated compression percentage.

How to Use the JavaScript Minifier

Using the tool is straightforward:

  • Paste your JavaScript into the Original JavaScript box.
  • Click Minify JavaScript to process your code.
  • Review the output in the Minified JavaScript box.
  • Use Copy Minified JS to copy the result, or Download .min.js to save it as a file.
  • Check the stats panel to see how much size you saved.

Privacy-Friendly, Client-Side Minification

All minification happens locally in your browser using JavaScript. Your code is not uploaded, logged or stored on any server. This makes the tool safe to use with private, proprietary or client-side scripts.

Best Practices for Production JavaScript

  • Keep a readable, well-structured version of your code in your repository.
  • Serve the minified version (e.g. app.min.js) on live sites and CDNs.
  • Combine minification with HTTP compression (Gzip/Brotli) at server level.
  • Remove unused JS where possible to reduce parsing and execution time.
  • For large applications, consider using a bundler like Webpack, Rollup, esbuild or Vite and use this tool for quick checks or small scripts.