How the JSON Schema Validator Works

What the Tool Does

This JSON Schema validator checks JSON data against a JSON Schema (draft-04, draft-06, draft-07, or 2019-09). It reports whether the data is valid, and when invalid it shows the path, keyword, and message for each error so you can fix the data or adjust the schema.

Common Developer Use Cases

Developers use a JSON Schema validator to test API request/response payloads, validate config files, generate or debug schema-based validation in code, and ensure OpenAPI or other schema-driven formats are correct. It is also useful when building forms or ETL pipelines that rely on JSON Schema.

Schema and Data Input

Paste or load your JSON Schema in one panel and your JSON data in the other. The tool parses both and runs validation. Supported schema versions are detected from the "$schema" keyword. Invalid JSON in either panel is reported before validation runs.

Common Pitfalls and Edge Cases

Ensure the schema itself is valid JSON and uses a supported "$schema" URL. Empty or non-object data can be valid or invalid depending on the schema (e.g. required fields, type constraints). Nested errors are shown with path notation; fix one error and re-run to see remaining issues.

When to Use This Tool vs Code

Use this validator for quick checks, debugging, and exploring schemas. For production, run validation in your app with a library like Ajv or similar, and keep schema and validation logic in version control and tests.