Free Online JSON Validator
Paste or upload JSON to check whether it is valid. Errors show line, column, snippet, and suggestions—processed locally in your browser.
JSON input
Features
Live validation
Syntax is checked as you type—no button required.
Precise errors
Line, column, snippet, and common fix hints.
Private
Data stays in your browser; nothing is uploaded.
FAQ
- Validator vs formatter?
- Validation only checks syntax. Formatting also beautifies output. This tool focuses on validity.
- File size limit?
- Upload up to 4 MB text files. Split very large payloads if needed.