JSON Schema Validator
Validate your JSON data against a JSON Schema. Ensure your data conforms to a defined structure with detailed error reporting.
JSON Data
JSON Schema
Validation Result
Enter JSON data and schema, then click Validate
What is JSON Schema Validation?
JSON Schema is a vocabulary for defining the structure, content, and semantics of JSON data. A JSON Schema validator checks whether your data conforms to a given schema definition. JSONKit uses the Ajv library for fast, spec-compliant validation with detailed error messages pointing to exact locations of violations.
How to use
- Paste your JSON data into the data editor, or click Load Example to start with a sample.
- Paste the JSON Schema that describes the expected structure into the schema editor.
- Click Validate.
- Read the list of errors. Each one shows where in the data the problem is and which schema rule failed.
Features
- Validation powered by Ajv, one of the most widely used JSON Schema validators.
- Supports JSON Schema draft-07, including common formats such as email, date-time, uri and uuid.
- Reports all errors at once instead of stopping at the first one.
- Data and schema stay in your browser.
Frequently asked questions
- What is JSON Schema?
- JSON Schema is a vocabulary for describing the structure of JSON data: which properties are required, what type each value must be, allowed ranges, string patterns and more. It is widely used for API contracts and configuration validation.
- Which JSON Schema version is supported?
- The validator uses the draft-07 specification, which is compatible with most schemas in use today, including those generated by many tools and the OpenAPI ecosystem.
- Why does my data fail with "must have required property"?
- The schema lists that property under required, but it is missing from the data. Either add the property to the data or remove it from the required array in the schema.