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CSS & JS Minifier – Minify Code Online Free

Minify CSS and JavaScript files online for free. Reduce file size instantly with size savings percentage shown—copy or download your minified output. Browser-based, no uploads.

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About This Tool

Learn what makes this tool special

Our CSS & JS Minifier reduces the file size of your CSS and JavaScript code by removing unnecessary characters — whitespace, comments, and applying safe optimizations — making your website faster.

Why Minify CSS and JavaScript?


- Faster page load: smaller files download quicker
- Better Core Web Vitals: LCP and FID improve with smaller JS bundles
- Reduced bandwidth: less data transferred per page view
- Better SEO: Google uses page speed as a ranking factor

CSS Minification Removes


- Whitespace and line breaks
- Comments (/ ... /)
- Redundant semicolons
- Shortens hex colors (#FFFFFF → #FFF)
- Removes zero units (0px → 0)

JavaScript Minification Does


- Removes whitespace and comments
- Shortens local variable names
- Removes dead code

Size Savings


Typical CSS minification reduces file size by 20–40%. JS minification with variable renaming can reduce size by 30–60%.

When to Minify


Always minify production CSS and JS. Keep source (unminified) copies for development. Build tools like webpack and Vite do this automatically in production builds.

Key Features

What makes this tool special

  • Minify CSS — removes whitespace, comments, shortens values
  • Minify JavaScript — removes whitespace and comments
  • Shows original and minified file sizes
  • Percentage size reduction shown
  • Copy minified code to clipboard
  • Paste code directly or type in the editor
  • No sign-up required
  • 100% browser-based — code never uploaded
  • Free with no limits
  • Handles large files efficiently
  • Mobile-friendly interface

Quick Guide

Master this tool in seconds

  1. 1
    Select CSS or JavaScript as the code type
  2. 2
    Paste your CSS or JS code into the input area
  3. 3
    Click 'Minify' to process the code
  4. 4
    The minified output appears in the result area
  5. 5
    See the file size before and after, and the % reduction
  6. 6
    Click 'Copy' to copy the minified code
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Common Questions

Everything you need to know

Q.Is CSS and JS minification safe?

A.

Yes — minification only removes whitespace, comments, and performs safe syntax-level optimizations. The code behaves identically.

Q.Will minified code still work the same?

A.

Yes. Minification does not change the logic or functionality of code — it only removes characters that computers don't need to execute it.

Q.How much does minification reduce file size?

A.

CSS typically reduces 20–40%. JavaScript typically reduces 30–60% with variable renaming. Savings vary by codebase.

Q.Can I minify HTML too?

A.

This tool focuses on CSS and JavaScript. For HTML minification, use a dedicated HTML minifier.

Q.Should I keep the original (unminified) code?

A.

Yes — always keep source files. Minified code is hard to read and debug. Use minified versions only for production deployment.

Q.Is my code sent to a server?

A.

No. All minification runs in your browser. Your code never leaves your device.

Q.Is this minifier free?

A.

Yes — completely free with no sign-up.

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