JavaScript Formatter & Minifier

Make JavaScript Readable — or Smaller

Whether you’re debugging a minified script from a live site, reviewing a snippet from Stack Overflow, or cleaning up your own code, readable JavaScript saves time. This formatter re-indents your code with consistent spacing so functions, loops and conditions are clearly structured. When you need the opposite, the minifier strips whitespace and comments to make the file as small as possible.

How to Use the JavaScript Formatter

1. Paste your JavaScript into the input editor, or click Load Sample.
2. Choose 2, 3 or 4 spaces for indentation.
3. Click Format / Beautify or Minify / Compress.
4. Copy the result.

Before and After

Minified:

function emi(p,r,n){const m=r/1200;if(m===0)return p/n;return p*m*Math.pow(1+m,n)/(Math.pow(1+m,n)-1)}console.log(emi(500000,8.5,60).toFixed(0));

Formatted:

function emi(p, r, n) {
  const m = r / 1200;
  if (m === 0) return p / n;
  return p * m * Math.pow(1 + m, n) / (Math.pow(1 + m, n) - 1);
}
console.log(emi(500000, 8.5, 60).toFixed(0));

(This small function is the same formula our EMI Calculator uses — it prints 10258.)

Why Formatting Helps

• Debugging: browser errors point to a line number. In a one-line minified file every error is on “line 1”; formatted code makes the location meaningful.
• Code review: consistent style lets reviewers focus on logic, not spacing.
• Learning: formatting third-party scripts is a great way to see how other developers structure their code.

Why Minify JavaScript?

JavaScript has to be downloaded, parsed and executed before a page becomes interactive. Smaller files help, especially on budget phones and mobile data. Minification typically cuts file size by 30–60% before compression. For production sites, combine it with:

• Server compression (gzip or Brotli).
• Loading scripts with defer so they don’t block rendering.
• Removing unused libraries and code.

JavaScript Style Tips

• Prefer const and let over var.
• Use strict equality (===) to avoid surprising type conversions.
• Give variables descriptive names; let the minifier make them short later.
• Keep functions small and focused on one task.
• Use a linter such as ESLint and a formatter such as Prettier in larger projects so the whole team’s code looks the same.

Related Tools

• JSON Formatter — validate and beautify JSON data.
• HTML Formatter — tidy markup.
• CSS Formatter — beautify or minify stylesheets.