JSON Validator Online
Paste JSON below to check syntax and find errors instantly
About This Tool
JSON validation is a critical step in any API development or data processing workflow. A single missing comma, mismatched bracket, or unquoted key can break an entire application. Our free online JSON validator checks your JSON against the official JSON specification and instantly reports any syntax errors with precise location information — exact line number and character position. Unlike basic validators that just say 'invalid JSON', JSONView tells you exactly where the problem is and what caused it. Paste any JSON — from API responses, configuration files, webhook payloads, or database exports — and get instant feedback. Valid JSON is confirmed with a clear success message. Invalid JSON shows a detailed error message so you can fix it immediately. The validator also shows useful statistics: total keys, nesting depth, and array sizes. Works entirely in your browser with no data sent to any server.
How to Use
- Paste your JSON into the input area above
- Click Validate or press Ctrl+Enter
- Green means valid. Red shows the exact error location.