JavaScript Input
Formatting Options
Spacing and layout
JavaScript and advanced formatting
Beautified Output
// Beautified JavaScript preview appears here.
| Measurement | Before | After |
|---|---|---|
| Characters | 0 | 0 |
| Lines | 1 | 1 |
| Bytes | 0 | 0 |
How to use this JS Beautifier
Paste JavaScript or upload a supported file. Choose a preset or customize formatting. Press Beautify JavaScript to format the code. Review validation messages before copying or downloading the result.
Keyboard shortcuts: Ctrl + Enter beautifies code. Ctrl + F focuses search inside the output editor. Tab inserts indentation inside either editor.
Formatting approach
This tool uses a browser-side tokenizer and formatter. It understands strings, comments, template literals, brackets, blocks, common operators, functions, classes, loops, imports, exports, objects, arrays, promises, async syntax, destructuring, optional chaining, spread operators, and modern JavaScript punctuation.
Basic validation checks balanced delimiters, strings, templates, and comments. Full JavaScript parsing requires a dedicated standards-compliant parser, so complex syntax errors can still need a developer toolchain.