Formatters

JavaScript Minifier/Beautifier

Minify, beautify, and validate JavaScript code with customizable options

JavaScript Input

Preset

Indent

Compat

Semicolons

Quotes

Wrap at

Remove comments Remove console.log Remove debugger

Preserve names:

About

Minifies and beautifies JavaScript code with variable name shortening to reduce size, while allowing preserve names to protect specific identifiers. Removes console.log, debugger statements, and comments, with ES5/ES6+ compatibility modes. Shows a size comparison between original and minified output with percentage savings.

Shipping large JavaScript files hurts page performance, and production builds need aggressive minification. This tool provides fine-grained control over what gets stripped and what gets preserved, with a visual size comparison to quantify savings.

Who should use this tool?

Frontend developers optimizing JavaScript bundles, build pipeline maintainers, and anyone shipping JavaScript to production who needs to reduce file size.

Common use cases

Minify a JavaScript library before publishing to npm with variable shortening enabled
Strip all console.log and debugger statements from development code before production deployment
Use preserve names to keep specific function names unmangled for external API compatibility
Beautify minified JavaScript from a CDN to debug a production issue
Switch between ES5 and ES6+ compatibility to ensure output works in target browsers

How to Use

Paste JavaScript code into the input area or upload a .js file

Select Mode: Minify (compress) or Beautify (format)

Toggle options: variable shortening, preserve names list, remove console, remove debugger, remove comments

Choose compatibility: ES5 (e.g. var instead of let/const, avoid arrow functions) or ES6+ (modern JS)

Click Process to generate the output; review the size comparison showing original KB, minified KB, and % savings

Copy the result or download as a .min.js file

Examples

Input: 'function add(a, b) { console.log("adding"); return a + b; }' with shorten and remove console. Output: 'function x(a,b){return a+b}'

Input: Minified JS from CDN with beautify mode. Output: Formatted and indented JavaScript with proper line breaks.

Best Practices

Use preserve names for any function or variable accessed via dynamic property names or eval
Always run tests after minification with variable shortening to ensure nothing broke
Use ES5 mode if targeting older browsers; ES6+ mode produces smaller output for modern targets
Strip console.log only in production builds; keep them during development

Common Mistakes

Shortening variable names without preserving exported symbols, causing runtime ReferenceErrors
Removing console.log globally when some logging is needed for production monitoring
Using ES6+ mode and deploying to a browser that doesn't support modern syntax
Assuming beautification produces the original code; comments and formatting are permanently lost

FAQ

Can variable shortening be reversed? No, shortened variable names lose their original names permanently.

Does it handle ES modules? Yes, import/export statements are preserved during minification.

What size reductions are typical? 30-70% depending on variable shortening and comment removal.

Can I minify TypeScript? The tool expects JavaScript; compile TypeScript to JS first.

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Learning Resources

Dive deeper with our comprehensive guides and tutorials.

JavaScript Minifier/Beautifier - Beginner's Guide

5 min read

JavaScript Minifier/Beautifier Advanced Techniques

8 min read

JavaScript Minifier/Beautifier

Minify, beautify, and validate JavaScript code with customizable options

JavaScript Input

Preset

Indent

Compat

Semicolons

Quotes

Wrap at

Remove comments Remove console.log Remove debugger

Preserve names:

About

Who should use this tool?

Frontend developers optimizing JavaScript bundles, build pipeline maintainers, and anyone shipping JavaScript to production who needs to reduce file size.

Common use cases

Minify a JavaScript library before publishing to npm with variable shortening enabled
Strip all console.log and debugger statements from development code before production deployment
Use preserve names to keep specific function names unmangled for external API compatibility
Beautify minified JavaScript from a CDN to debug a production issue
Switch between ES5 and ES6+ compatibility to ensure output works in target browsers

How to Use

Paste JavaScript code into the input area or upload a .js file

Select Mode: Minify (compress) or Beautify (format)

Toggle options: variable shortening, preserve names list, remove console, remove debugger, remove comments

Choose compatibility: ES5 (e.g. var instead of let/const, avoid arrow functions) or ES6+ (modern JS)

Click Process to generate the output; review the size comparison showing original KB, minified KB, and % savings

Copy the result or download as a .min.js file

Best Practices

Use preserve names for any function or variable accessed via dynamic property names or eval

Always run tests after minification with variable shortening to ensure nothing broke

Use ES5 mode if targeting older browsers; ES6+ mode produces smaller output for modern targets

Strip console.log only in production builds; keep them during development

Common Mistakes

Shortening variable names without preserving exported symbols, causing runtime ReferenceErrors

Removing console.log globally when some logging is needed for production monitoring

Using ES6+ mode and deploying to a browser that doesn't support modern syntax

Assuming beautification produces the original code; comments and formatting are permanently lost

FAQ

Can variable shortening be reversed? No, shortened variable names lose their original names permanently.

Does it handle ES modules? Yes, import/export statements are preserved during minification.

What size reductions are typical? 30-70% depending on variable shortening and comment removal.

Can I minify TypeScript? The tool expects JavaScript; compile TypeScript to JS first.

JavaScript Minifier/Beautifier

About

Who should use this tool?

Common use cases

How to Use

Examples

Best Practices

Common Mistakes

FAQ

Related Tools

Same Category — Formatters

JSON Formatter

SQL Formatter

HTML Formatter/Validator

CSS Formatter/Minifier

Popular Tools

Base64 Encoder/Decoder

JWT Decoder

URL Encoder/Decoder

Learning Resources

Share

JavaScript Minifier/Beautifier

About

Who should use this tool?

Common use cases

How to Use

Examples

Best Practices

Common Mistakes

FAQ

Related Tools

Same Category — Formatters

JSON Formatter

SQL Formatter

HTML Formatter/Validator

CSS Formatter/Minifier

Popular Tools

Base64 Encoder/Decoder

JWT Decoder

URL Encoder/Decoder

Learning Resources

Share