Free JSON Formatter & Validator Online

Format, validate, and minify JSON instantly. Convert JSON to CSV and view as tree or table. Free online JSON formatter and validator for developers. No signup required.

How to Use Free JSON Formatter & Validator Online

  1. Paste your raw or minified JSON into the input field on the left
  2. Click Format to beautify with indentation, or Minify to compress for production
  3. Switch to tree view to expand and collapse nested objects and arrays
  4. Click Convert to CSV to turn a JSON array of objects into a spreadsheet-ready file

Frequently Asked Questions

What is JSON and why format it?

JSON (JavaScript Object Notation) is a lightweight data format. Raw JSON from APIs is often minified (no spaces) and hard to read. Formatting adds indentation and line breaks to make it human-readable for debugging and development.

How do I validate a JSON file?

Paste your JSON in our validator. Valid JSON shows a green ✅ confirmation. Invalid JSON shows the exact line and column of the error with a description of the problem — no guessing required.

What is the difference between JSON and JSON5?

Standard JSON requires double-quoted strings and no trailing commas. JSON5 is a superset that allows comments, single quotes, and trailing commas. Our validator checks standard JSON compliance.

How do I convert JSON to a spreadsheet?

Paste a JSON array of objects into our formatter and click 'Convert to CSV'. The result is a comma-separated file ready to open in Excel, Google Sheets, or any spreadsheet application.

Is this JSON formatter safe to use?

Yes, all JSON processing happens in your browser using native JSON.parse(). Your data never leaves your computer or gets sent to any server.

Can I format a large JSON file?

Yes, our formatter handles large JSON files (several MB) entirely in your browser. For files over 10 MB, use the Minify option first to reduce size. No upload limits and no server timeouts apply.