JSON Schema Validator
Paste JSON data and a JSON Schema to validate it locally. Errors include the path and the rule that failed.
About JSON Schema Validator
Validate JSON against a JSON Schema online and get precise error paths and messages for every failing rule. This free JSON Schema validator helps you test required properties, data types, enums, formats, nested object constraints, and array item rules before your data reaches an API or database. It is useful for debugging request payloads, OpenAPI models, and configuration contracts.
API designers paste a schema and a sample body to see why a gateway rejected a request. Frontend developers check form output against the contract. QA builds fixtures that should fail on purpose and confirms the right path is reported. Backend teams reproduce a production validation error without standing up the service. Error paths make nested failures obvious, such as items[2].email rather than a generic invalid payload.
Provide both the schema and the instance JSON. When they are valid together, you get a clear pass. When they are not, you get rule-level messages you can fix in either the data or the schema. This is more precise than only checking that JSON parses. Pair it with the JSON viewer or JSON beautifier to inspect the instance while you work.
Your schema and data are validated in your browser and never uploaded. Internal API contracts stay on your device. Use this free online JSON Schema validator whenever you need path-accurate, private schema checks.