JSON Formatter & Validator
Pretty-print JSON with indentation, and get a clear error message if it's invalid.
Paste JSON to format it with readable indentation, or catch a syntax error immediately — the tool tells you exactly what's wrong and roughly where, using the browser's own JSON parser.
Your files and text are processed locally in your browser — nothing is uploaded to a server.
JSON Formatter & Validator tool
How to Use JSON Formatter & Validator
- Paste your JSON into the input box.
- Click Format & Validate.
- Fix any reported error, or copy the formatted output.
Features
- Pretty-prints with adjustable indentation
- Clear error messages for invalid JSON
- Copy formatted result with one click
- Runs entirely in your browser
Frequently Asked Questions
Does this tool validate against a schema?
No, it validates that the JSON is syntactically well-formed, not against any specific schema.
Is my JSON data uploaded anywhere?
No, parsing and formatting happen locally using your browser's built-in JSON support.