How do I check JSON for syntax errors?
Paste your JSON on the DevTools JSON Validator page and click Validate. The page shows the parser error and its position.
JSON Validator
DevTools JSON Validator checks whether JSON syntax is valid and reports line, column, and error details when parsing fails—all in your browser, with no upload.
JSON input
About this tool
Validate JSON before submitting configs or debugging APIs to catch parse errors early and avoid runtime failures.
How to use
- Paste the JSON to validate.
- Click Validate.
- Fix errors at the reported position and re-validate.
FAQ
Does the validator support JSON5?
No. Only standard JSON is accepted—double-quoted keys, no trailing commas, and strict syntax rules.
Does passing validation mean my data is correct?
No. Valid syntax does not guarantee complete fields or correct types. Combine with JSON Schema or business rules for full checks.
Is validation done on a server?
No. Validation runs entirely in your browser using the native JSON parser.
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