Developer Tools

JSON Formatter & Beautifier

Paste any JSON (minified, escaped, or messy) and get clean, readable output in milliseconds. The formatter validates syntax as you type, highlights errors with line numbers, and lets you choose your indentation level.

Instant pretty-print Validates while formatting 2 / 4 spaces or tabs
json JSON (any format)
Options
Runs in your browser; code never leaves your device

Features

  • Formats JSON with 2 or 4-space indentation
  • Real-time syntax validation with exact error location
  • Minify mode to compact JSON for production use
  • Sorts keys alphabetically (optional)
  • Copy formatted output or download as .json
  • Handles JSON with trailing commas and comments (lenient mode)

How to use it

  1. Paste your raw JSON into the input panel.
  2. The formatted output appears instantly in the right panel.
  3. If there is a syntax error, the error bar shows the exact line and column.
  4. Use the Minify button to compact JSON for copying into code.
  5. Click Copy or Download to save the result.

Use cases

  • Reading minified API responses during development
  • Reviewing JSON config files before deployment
  • Debugging JSON payloads from curl or Postman
  • Prettifying JSON log entries for readability

Limitations

  • Invalid JSON shows an error instead of being changed silently.
  • Very large input can be slower on older devices.
  • This utility is designed for common snippets and local inspection, not as a full security or language-specific validator.
See also

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Questions & answers

Frequently asked

Does it fix invalid JSON automatically?

In strict mode it reports errors. In lenient mode it can handle trailing commas and // comments (common in JSON5 or config files).

Is there a size limit?

No server limit. The browser handles it. Files up to several MB format instantly; very large files may take a second.