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CSS/JS Minifier

Minify and beautify CSS and JavaScript code

Input
CSS
Output

How to Use

1

Paste or Type Input

Enter your text, code, or data into the input area.

2

Choose Options

Select the transformation or format you want to apply.

3

Copy the Result

Copy the output to your clipboard with one click.

Why Use This Tool

100% Free

No hidden costs, no premium tiers — every feature is free.

No Installation

Runs entirely in your browser. No software to download or install.

Private & Secure

Your data never leaves your device. Nothing is uploaded to any server.

Works on Mobile

Fully responsive — use on your phone, tablet, or desktop.

IT & Developer Guide

CSS and JavaScript Minification for Web Performance

Key Takeaways

  • Minification removes whitespace, comments, and unnecessary characters to reduce file sizes by 20–60% on average.
  • Smaller CSS and JavaScript files mean faster page loads, especially on mobile networks with limited bandwidth.
  • All minification runs in your browser — your source code stays completely private.

Every kilobyte matters for web performance. CSS and JavaScript minification is a fundamental optimization that strips unnecessary characters from source code without changing functionality. While build tools like Webpack and Vite handle this automatically in production pipelines, a quick online minifier is invaluable for one-off optimizations, email templates, and embedded scripts.

Minification typically reduces CSS file sizes by 20–40% and JavaScript by 30–60%.

Size Reduction

Common Use Cases

1

Email Template Optimization

Minify inline CSS in HTML email templates to stay under email client size limits and improve rendering speed.

2

Third-Party Script Embedding

Minify JavaScript snippets before embedding them as inline scripts in CMS platforms or widget integrations.

3

Performance Auditing

Quickly check how much size reduction minification would achieve for files flagged in Lighthouse performance audits.

4

CDN Payload Optimization

Minify static assets before uploading to CDNs that do not offer automatic minification at the edge.

Pro Tips

Always keep your original unminified source files in version control — minified code should only be used in production.

Combine minification with gzip or Brotli compression for maximum file size reduction — they complement each other well.

Test minified code thoroughly, as aggressive minification can occasionally break CSS specificity or JavaScript variable scoping.

Use source maps in development to debug minified code by mapping it back to the original readable source.

All CSS and JavaScript minification is performed entirely in your browser. Your source code is never uploaded to any server, ensuring your proprietary code and business logic remain completely private.

Frequently Asked Questions