1. Paste your JSON Schema definition in the Schema editor
2. Paste the JSON data you want to validate in the Data editor
3. Click "Validate" to run the validation
4. Review the result (pass/fail) with detailed error messages
5. Supports type, required, minimum/maximum, minLength/maxLength, pattern, enum, properties and more
JSON Schema is a declarative language for describing the structure of JSON data. It allows you to define constraints like field types, required fields, value ranges, regex patterns, and more. It's widely used for API documentation, data validation, and configuration file checking — similar to what XML Schema is for XML.
Most commonly used keywords are supported: type (string/number/integer/boolean/array/object/null), properties, required, items, minItems/maxItems, minimum/maximum, minLength/maxLength, pattern, enum, default, description, $ref (basic), oneOf, anyOf, allOf, not, const, dependencies, and more. Nested objects and arrays are fully supported.
No. This tool runs entirely in your browser. All data is processed locally and never uploaded to any server. Your JSON data and Schema stay completely private.