JSON Validator
Validate JSON online and get a precise error message with the position of the problem. Fast, local and free.
How to use
- 1
Paste your JSON.
- 2
Click "Validate".
- 3
See Valid, or an error that names what went wrong and where.
How it works
The JSON is parsed with the native parser; a throw is caught and turned into a readable message with line and column. Useful for debugging API responses and config files.
Frequently asked questions
What makes JSON invalid?
Common causes: trailing commas, single quotes, comments, unquoted keys and mismatched brackets.
Can it tell me the exact position?
Yes - the error message includes the character offset and a snippet around it.
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