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JavaScript Beautifier

Reformat dense JavaScript into readable code locally for debugging.

JavaScript Beautifier
Processed entirely in your browser. No uploads, no background processing, and no account required.
Ctrl+Enter Beautify Ctrl+Shift+Enter Validate Ctrl+Shift+C Copy
JavaScript input Editable input
1 line | 0 chars | 0.0 KB
Beautified JavaScript Read only output
1 line | 0 chars | 0.0 KB
Ready Browser only
Paste content into the input editor and run an action.

How ZeroData protects your privacy

  • ✓ No Uploads: Tool input is processed in your browser and is not sent to ZeroData servers.
  • ✓ No Storage: Tool input is not saved by this website.
  • ✓ No Input Tracking: Analytics never receive the text, files, keys, or credentials you process.
  • ✓ Verifiable: Disconnect from the network after the page loads; local tool processing continues without uploading your input.

How to Use the JavaScript Beautifier

  1. Paste JavaScript into the input editor.
  2. Use Beautify to reformat the code with normalized spacing and indentation.
  3. Use Validate to check that the code parses cleanly.
  4. Copy or download the result once the output looks right.

Common Use Cases

  • De-minifying production JavaScript code to debug a console error occurring only on the live website.
  • Formatting an inherited, messy legacy JavaScript file to make it readable before beginning a refactor.
  • Auditing a third-party tracking script or widget for privacy concerns or malicious activity.
  • Standardizing the code style of a script before submitting it for a team code review.
  • Extracting and understanding the logic of a complex JSON object or configuration embedded in a JS file.

Frequently Asked Questions

Will beautifying my JavaScript change how it executes?

No, beautifying only alters the whitespace, indentation, and formatting of the code. The underlying logic, variable names, and execution order remain completely unchanged.

Can this tool decode heavily obfuscated JavaScript?

The beautifier will correctly indent and format obfuscated code, making the structure visible. However, it will not rename mangled variables (e.g., changing 'a' back to 'userData') or decrypt encoded strings.

Does the beautifier support modern ES6+ syntax?

Yes, it fully supports modern ECMAScript features including arrow functions, classes, async/await, and template literals.

Can I use this tool to format JSON files?

Yes, because JSON is a subset of JavaScript object syntax, the beautifier will perfectly format raw or minified JSON strings into a readable structure.

Is it safe to paste code containing API keys into this tool?

Yes. The tool processes everything locally in your browser. Your code, including any sensitive keys or tokens, is never sent over the network to any server.

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