DEV Developer Toolkit

JavaScript Minifier

Compress JavaScript code by removing whitespace, comments, and shortening variable names.

Text Utilities
Drop a .js file here

How to use JavaScript Minifier

The JavaScript Minifier compresses your JavaScript code by removing comments, unnecessary spaces, and formatting. This reduces file size, speeds up downloads, and improves page load performance.

What gets removed:

  • Single-line comments (// comment)
  • Multi-line comments (/* comment */)
  • Unnecessary whitespace and line breaks
  • Extra spaces around operators
  • Trailing semicolons in appropriate places

Example:

Before (2.5KB):

// Initialize application
function initApp() {
  // Get DOM elements
  const btn = document.getElementById('btn');
  
  // Add click handler
  btn.addEventListener('click', function() {
    console.log('Button clicked!');
  });
}

After (0.9KB, 64% reduction):

function initApp(){const btn=document.getElementById('btn');btn.addEventListener('click',function(){console.log('Button clicked!')})}

FAQs

Does minification break my JavaScript?

No. Minification only removes comments and unnecessary formatting. Your code will function identically.

How much reduction can I expect?

Most JavaScript files see 30-50% size reduction, depending on comment density and formatting style.

Can I still debug minified code?

Yes, but stack traces become harder to read. Consider keeping source maps for debugging.

What about sensitive code?

Minification provides no security—it's only for size optimization. Use proper access controls and encryption for sensitive data.