📖 What is JS Minifier?
JavaScript Minifier compresses your JS code by removing whitespace, comments, and unnecessary characters. The result is a smaller file that loads and parses faster in the browser, improving page performance. Paste your JavaScript and get minified output instantly. Everything runs in your browser — your code is never uploaded.
💡 Example
Input
function greet(name) {
// Say hello
console.log("Hello, " + name);
}
Output
function greet(n){console.log("Hello, "+n)}
🛠️ Common Use Cases
- Reducing JavaScript file size before production deployment
- Quick-checking compression ratio without a build tool
- Minifying inline scripts for HTML pages
- Preparing JS for embedding in email templates or widgets
- Comparing original vs minified size
📝 What JS Minification Does
- Removes whitespace, newlines and comments
- Shortens variable and function names (in advanced minifiers)
- Removes unnecessary semicolons and brackets
- Simplifies expressions where possible
For production, use build tools like Terser, esbuild or webpack — they perform additional optimizations like dead code elimination and tree shaking.
⚠️ Common Mistakes
- Minifying during development — always work with readable code and only minify for production. Use source maps for debugging.
- Breaking ASI (Automatic Semicolon Insertion) — some minification can break code that relies on ASI. Always use explicit semicolons.
- Not testing — minification rarely breaks code, but test the output before deploying.
❓ Frequently Asked Questions
How much smaller will my JavaScript get? ▾
Typical savings are 30-60% from minification. Combined with gzip, total savings reach 70-90%.
Will minified code work the same? ▾
Yes — minification only removes characters that do not affect execution. The logic is identical.
Should I use this instead of a build tool? ▾
For production, use Terser, esbuild or webpack. Use this tool for quick one-off minification or checking compression ratios.
Is my data private? ▾
Yes — all processing runs entirely in your browser. Your data is never sent to any server.
Is this tool free? ▾
Completely free — no login, no usage limits, works offline once loaded.
Yes — completely free, no login required, no usage limits.
Is my data private? ▾
Yes — all processing runs in your browser. Your data is never sent to any server.
Does it work offline? ▾
Yes — once the page is loaded, the tool works without an internet connection.