Check JSON syntax and pinpoint errors by line and column before deploying to production.
JSON Validator is a free online tool that checks whether your JSON is syntactically valid and pinpoints any error by line and column. It is useful for API responses, webhook payloads, configuration files, and mock data. The tool runs in your browser and does not send data to the server.
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JSON Validator checks JSON syntax and helps you quickly find errors in API responses, webhook payloads, configuration files, mock data, or objects before deploying to production. The tool shows a clear validity status, the error message, position, line, column, and a snippet around the problem.
For valid JSON, the service shows structural statistics: document size, root type, number of objects, arrays, keys, and maximum nesting depth.
All processing is done locally in the browser. Your data is not sent to the server.