How it works
The JSON Schema Validator checks whether a JSON document conforms to a given JSON Schema definition, reporting every validation error β missing required fields, wrong types, pattern mismatches, out-of-range values β with the exact path to the offending field.
JSON Schema is the standard way to formally define the shape of JSON data: required fields, allowed types, string patterns, numeric ranges, enum values, and nested object/array structures. It's used to validate API request/response bodies, configuration files, and data pipeline payloads before they're processed.
How to use it: paste your JSON Schema (draft-07 and 2020-12 are both supported) into the schema panel, and the JSON document you want to validate into the data panel. Click "Validate" and the tool lists every violation found, each with a JSON Pointer path (like "/user/address/zipCode") so you can locate the exact field, plus a human-readable explanation of what rule was violated and what was expected instead.
Common uses: verifying an API response matches its documented schema during debugging, validating a config file before deploying it, checking that test fixtures conform to the same schema used in production validation, and learning JSON Schema syntax by experimenting with a schema and seeing which inputs pass or fail.
Privacy: schema compilation and validation run entirely in your browser using a JSON Schema validation library compiled to run client-side. Neither your schema nor your data is ever transmitted anywhere.
Frequently Asked Questions
- The validator supports both draft-07 and the 2020-12 specification, covering the keywords and validation rules most commonly used in modern APIs and tooling.
- Each error includes a JSON Pointer path (such as '/user/address/zipCode') pointing to the exact location in your data, along with a description of which schema rule was violated.
- Yes. Define your schema with 'type: array' and an 'items' schema describing the shape of each element β the validator checks every item in the array and reports errors per index.
- It validates that your schema is itself well-formed JSON Schema before checking your data against it. If the schema has structural problems, that's reported separately from data validation errors.