JavaScript Beautifier

Beautify, format, minify, and syntax-check JavaScript or JSX online. Clean messy code, improve readability, control common style options, and download formatted output directly in your browser.

Syntax checking is parser-based only. It does not replace linting, runtime testing, or full application validation.

Beautifier Controls

Format, minify, or syntax-check JavaScript and JSX in your browser. Syntax checking uses the formatter parser and does not replace linting or runtime testing.

Output mode

358 chars · 15 lines
0 chars · 1 lines

Status

Paste JavaScript or JSX and click beautify, minify, or syntax check.

Current mode

beautify

Indentation

2 spaces

Line width

80

Error location

-

Included features

  • Beautify and minify JavaScript or JSX in the browser.
  • Browser-based syntax checking using the formatter parser.
  • Line numbers in both input and output editors.
  • Aligned line numbers with fixed editor spacing.
  • Upload .js, .jsx, .mjs, and .cjs files.
  • Control semicolons, quotes, trailing commas, and line width.
  • Copy or download formatted output.

JavaScript syntax details

Paste JavaScript or JSX and click beautify, minify, or syntax check.

An exact line and column could not be detected from the parser message.

Total input lines: 15

What can this JavaScript beautifier do?

This tool formats JavaScript and JSX for readability, minifies code for compact output, and performs browser-based syntax checking using the formatter parser. You can control tab width, semicolons, quote style, trailing commas, arrow function parentheses, and line width.

How to use

  1. Paste JavaScript or JSX into the input editor.
  2. Select beautify or minify mode.
  3. Adjust formatting options such as quotes and semicolons.
  4. Click the main button to format, or use syntax check.
  5. Copy or download the output.

Common use cases

Use it for API scripts, React JSX snippets, frontend components, Node.js utilities, code cleanup before commits, documentation examples, and preparing readable code for teammates.

Related tools

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