What is Minification?

The process of removing unnecessary characters from code (whitespace, comments) to reduce file size.

Minification — Glossary

Technical Detail

Code minification removes whitespace, comments, shortens variable names (in JS), and applies optimizations like dead code elimination. JavaScript minifiers (Terser, esbuild) can reduce file size by 40-70%. CSS minifiers merge duplicate rules, shorten color values (#ffffff → #fff), and remove redundant units (0px → 0). Combined with Brotli compression, minified assets achieve total size reductions of 80-90%. Source maps (.map files) enable debugging minified code by mapping back to original sources.

Example

```javascript
// Simple CSS minifier
function minifyCSS(css) {
  return css
    .replace(/\/\*[\s\S]*?\*\//g, '')  // remove comments
    .replace(/\s+/g, ' ')                // collapse whitespace
    .replace(/\s*([{};:,])\s*/g, '$1')   // remove around symbols
    .trim();
}
// 1024 bytes → 612 bytes (40% reduction)
```

Categories

Minification

Technical Detail

Example

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