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JavaScript Minifier & Beautifier

Safely minify JavaScript (comments + whitespace) or beautify messy code — preserves strings, regex, and template literals. Runs in your browser. Free.

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💡 About this tool

  • Minify removes comments and unnecessary whitespace safely — strings, template literals, and regex are preserved, and line breaks are kept so automatic semicolon insertion is not affected.
  • Beautify re-indents minified or messy JavaScript to make it readable.
  • Runs entirely in your browser — your code is never uploaded. For aggressive production builds with variable mangling, use a bundler such as Terser or esbuild.

Free JavaScript Minifier & Beautifier

Minify JavaScript to shrink file size for production, or beautify minified and messy code into readable form. Paste your JS, click Minify or Beautify, and copy the result with a live byte count. It safely preserves strings, template literals, and regular expressions — and runs entirely in your browser.

What does minifying JavaScript do?

Minifying JavaScript removes the parts a browser does not need to run your code — comments, indentation, and unnecessary whitespace — producing a smaller file that downloads and parses faster. Smaller scripts mean quicker load times and better performance scores, which is why minification is a standard step before shipping JavaScript to production.

A safe, non-breaking minifier

Minifying JavaScript is riskier than CSS or HTML because whitespace and punctuation carry meaning. This tool is built to be safe:

  • Strings, template literals, and regular expressions are fully preserved.
  • Comment-like text inside strings (such as a URL with // or /*) is never removed by mistake.
  • Line breaks are kept, so automatic semicolon insertion (ASI) is not affected and your code keeps working.
  • Division and regex are correctly told apart, so expressions like a / b are not misread.

How to use the JavaScript minifier

Both directions take one click:

  • Paste your JavaScript into the input box.
  • Click Minify to strip comments and whitespace, or Beautify to re-indent.
  • Check the byte savings shown after minifying.
  • Copy or download the result.

How much smaller will my code get?

This tool performs safe minification — removing comments, indentation, and blank lines — which typically trims a meaningful percentage from well-commented, nicely formatted source. For maximum compression, production build tools also rename local variables and rewrite expressions (a process called mangling), which requires a full JavaScript parser. For that, use a bundler such as Terser or esbuild in your build pipeline; this tool is ideal for quick, safe reductions and for cleaning up code by hand.

Beautifying minified JavaScript

The Beautify option is just as useful in reverse. Paste a minified or one-line script and it is re-indented with consistent spacing and line breaks, keeping loops like for(;;) intact on a single line. It is perfect for inspecting third-party code, understanding a minified bundle, or tidying up JavaScript pasted from a snippet before you edit it.

Pro tip

Keep readable source in version control and minify as part of your deployment, not by hand each time. Use this tool for quick wins, prototypes, and inline scripts. For your stylesheets and markup, pair it with our CSS Minifier and HTML Minifier & Beautifier.

FAQ

Is this JavaScript Minifier free and private?
Yes. It is completely free and runs entirely in your browser, so your code is never uploaded or stored.
Will minifying break my JavaScript?
No. This minifier is deliberately conservative: it preserves strings, template literals, and regex, and keeps line breaks so automatic semicolon insertion is unaffected. Your code behaves the same after minifying.
What is the difference between minifying and beautifying?
Minifying removes comments and whitespace to reduce file size. Beautifying re-indents code with line breaks and spacing to make it readable for editing and debugging.
Does it rename variables like a full minifier?
No. It performs safe minification (comment and whitespace removal) without renaming variables. For variable mangling and maximum compression, use a build tool such as Terser or esbuild.
Does it handle regular expressions and template literals?
Yes. The tool correctly identifies regular expressions versus division, and preserves template literals and strings exactly, including any comment-like characters inside them.
Does minifying JavaScript help SEO?
Indirectly. Smaller scripts load and execute faster, improving page speed and Core Web Vitals, which support SEO — especially when combined with server compression like gzip or Brotli.
Can I beautify a minified script back to readable code?
Yes. Paste minified JavaScript and click Beautify to re-indent it. Note that variable names cannot be restored if they were already shortened by a production build tool.

Related tools

Pro tip: pair this tool with Upside Down Text Generator and Text Similarity Checker for a faster SEO workflow.