JavaScript Minifier

JavaScript Minifier & Compressor Online

Use this online JavaScript minifier to quickly minify, compress, and optimize your JS for production. Type, paste or upload files, choose the target ECMAScript version, and pick the parse, compress, and format options that match your build. The tool reduces payload while preserving runtime behavior and core functionality.

Core Features

• Minify to remove comments, whitespace, and redundant tokens
• Compress using advanced passes that drop dead code and remove unused items
• Mangle names to shorten variables and properties for maximum savings
• Choose Enclose to wrap output in a top level closure for safer bundles
• Parse options include bare returns, HTML5 comments, and shebang support
• Fine grain compress options such as collapse vars, evaluate, and many more
• Control console and debugger removal easily in compress options
• Runs fully in the browser so no server upload is required

How to use this online JS minifier

1. Write, paste or upload your JavaScript into the editor
2. Choose customization options as per you requirement
3. Click Minify JavaScript button
4. Preview the result, and download it

Why use a JavaScript minifier or optimizer

Smaller scripts mean faster downloads and better time to interactive. A minifier tool shrinks files by removing whitespace and comments and by shortening names.

A compressor goes further by evaluating constants, removing unreachable code, and merging statements. Use the JS minifier tool to reduce bandwidth and speed up page load, while keeping the original source in version control for development and debugging.

Balance size and traceability by tuning mangle and keep name settings. If you need clear stack traces, enable keep function names option. If you want maximum size reduction, allow mangling and enable compress inlines and dead code removal.

Key differences: original JS vs minified JS

• Original JS is readable and easy to debug with full identifiers and comments
• Minified JS removes comments and whitespace and shortens identifiers to save bytes
• Compressed JS may also evaluate constants, inline small functions, remove unused code, and change statement order to reduce size

Example 1: Simple function

function square(x) {
  // return square of x
  return x * x;
}

console.log(square(5));

function square(e){return e*e}console.log(square(5));

Example 2: Modern features and classes

function formatString(e, ...t) {
    return e.replace(/{(d+)}/g, (e, n) => void 0 !== t[n] ? t[n] : e)
}

function validateEmail(e) {
    return /^[a-zA-Z0-9._%+-]+@[a-zA-Z0-9.-]+.[a-zA-Z]{2,}$/.test(e)
}

function debounce(t, n) {
    let u;
    return (...e) => {
        clearTimeout(u), u = setTimeout(() => t(...e), n)
    }
}

function throttle(t, n) {
    let u = !1;
    return (...e) => {
        u || (t(...e), u = !0, setTimeout(() => u = !1, n))
    }
}
const a = formatString("Hello, {0}!", "World");
console.log(a);
const b = validateEmail("example@example.com");
console.log(b);
const debouncedLog = debounce(console.log, 500);
debouncedLog("Debounced");
const throttledLog = throttle(console.log, 500);
throttledLog("Throttled");

function formatString(o,...e){return o.replace(/{(d+)}/g,((o,t)=>void 0!==e[t]?e[t]:o))}function validateEmail(o){return/^[a-zA-Z0-9._%+-]+@[a-zA-Z0-9.-]+.[a-zA-Z]{2,}$/.test(o)}function debounce(o,e){let t;return(...n)=>{clearTimeout(t),t=setTimeout((()=>o(...n)),e)}}function throttle(o,e){let t=!1;return(...n)=>{t||(o(...n),t=!0,setTimeout((()=>t=!1),e))}}const a=formatString("Hello, {0}!","World");console.log(a);const b=validateEmail("example@example.com");console.log(b);const debouncedLog=debounce(console.log,500);debouncedLog("Debounced");const throttledLog=throttle(console.log,500);throttledLog("Throttled");

Example 3: Advanced bundle with dead code removal

const DEBUG = false;

function calc(a, b) {
  if (DEBUG) {
    console.log("debug mode");
  }
  return a + b;
}

function unused() {
  return "this will be removed";
}

export default function main() {
  console.log(calc(10, 20));
}

function calc(n,t){return n+t}console.log(calc(10,20));

Customization Options

Below are are all the JS optimization options available while cmopressing JavaScript.

Best Practices For JS Minification

• Keep original code in version control
• Minify JS for production only and keep readable builds for development
• Generate source maps for easier debugging, though not included in this JS minifier
• Test minified output across browsers and devices
• Review third-party libraries before heavy optimization
• Automate minification in CI with environment flags
• Use multiple passes only when necessary

Conclusion

This JavaScript minifier and compressor helps you shrink bundles and improve load time and runtime performance. Choose ECMAScript version and refine parse, compress, and format options to match your environment. Test the final output across devices and browsers before deploying to production.