JSON Validator
Check JSON syntax locally and see its root type, value count, and nesting depth.
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How to use JSON Validator
Check whether a document follows JSON syntax before using it in an application or API request. A successful check reports the shape of the parsed data.
- Paste the JSON you want to check.
- Run the validator.
- Fix any syntax errors in your source and validate again.
Good to know
- Syntax validation does not prove that data matches a schema or is trustworthy.
- The parser accepts duplicate keys and retains the last value.
- Documents beyond the shared size and complexity limits are rejected.
Common questions
Are comments allowed?
No. Standard JSON does not allow comments or trailing commas.
Can a JSON document be a single number?
Yes. Strings, numbers, booleans, arrays, objects, and null can all be valid JSON roots.
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