JSON Validator

Validate JSON and get precise, line-by-line error messages. Use it to catch subtle issues like trailing commas, comments, unescaped characters, and malformed numbers before shipping configs or API payloads. Runs entirely in your browser for privacy and can work offline when installed as a PWA.

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Examples

Valid JSON

Input

{"user":{"id":123,"name":"Ada"},"roles":["admin","editor"],"active":true,"meta":{"created":"2026-03-05T17:46:39Z"}}

Output

Valid JSON

Invalid JSON (trailing comma in array)

Input

{"a":1,"b":[2,3,],"note":"trailing comma in array"}

Output

Invalid JSON (trailing comma in array)

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