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JavaScript Minifier

A free online JavaScript minifier. Paste your JS code and instantly remove all comments (// and /* */), collapse whitespace, and reduce file size. Shows original size, minified size, and compression ratio. Side-by-side editor with copy and download buttons. Runs entirely in your browser — no code is uploaded.

Original: 762 B→Minified: 440 B−42% saved

Input JavaScript762 chars

Minified Output440 chars

function fibonacci(n){if(n<=0)return 0;if(n===1)return 1;let a=0,b=1;for(let i=2;i<=n;i++){let temp=a+b;a=b;b=temp;}return b;}const result=fibonacci(10);console.log("Fibonacci(10)=",result);function isPrime(num){if(num<2)return false;for(let i=2;i<=Math.sqrt(num);i++){if(num%i===0)return false;}return true;}var primes=[];let count=0;for(var i=2;count<10;i++){if(isPrime(i)){primes.push(i);count++;}}console.log("First 10 primes:",primes);

What this minifier does

🗑 Removes // comments

🗑 Removes /* */ comments

🔧 Collapses whitespace

📦 Strips blank lines

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