JSON Schema Validator
Validate JSON data against a JSON Schema (draft 7+). Detailed error reporting with paths. Free, runs 100% in your browser.
Reference
How does the JSON Schema validator work?
JSON Schema is a vocabulary for describing the structure of JSON data — types, required fields, value constraints (min/max, pattern, enum), and nested schemas. This tool implements a draft 7+ subset of validation: type checks (string, number, integer, boolean, array, object, null), constraints (minLength, maxLength, minimum, maximum, pattern, enum, const), composition (allOf, anyOf, oneOf, not), and recursive validation of properties and items. Errors include the JSON path of the offending value.
Common uses
- API contract testing — verify responses match your OpenAPI/Swagger schemas.
- Config validation — catch typos before deploying configuration files.
- Form validation — share schemas between frontend and backend validators.
- Data quality — validate ingested JSON files in ETL pipelines.
Privacy
All validation runs 100% in your browser. Schemas and data never leave your device.