JSON Schema Validator Online

JSON Schema is a vocabulary for describing the expected structure and constraints of JSON data. A schema can define property types, required fields, allowed values, nested structures, arrays, and other rules. Validation checks whether a JSON document satisfies those rules.

Provide both the JSON data and the JSON Schema, then run schema validation. The validator compares the data with the schema rules and reports where a value, property, type, or other constraint does not match. In the validator above, use the two editors and inspect the resulting error path when validation fails.

JSON Schema validation checks whether JSON data conforms to the rules declared by a schema. A validation error means the JSON is syntactically readable but violates at least one schema constraint, such as a missing required property, an incorrect type, or a value outside an allowed rule.

Paste the JSON document into the data editor and the schema into the schema editor, then run validation. If the data does not satisfy the schema, use the reported rule and path to locate the mismatch. The validator above keeps the data and schema side by side for this workflow.

Start by defining the top-level JSON type, then describe expected properties, their data types, and any constraints such as required fields, enums, array items, or nested objects. Build the schema incrementally and validate representative JSON examples as the rules become more specific.

The required keyword lists object properties that must be present for the instance to satisfy the schema. It does not define the property's type by itself; the property is normally described separately under properties, while required controls whether its presence is mandatory.