JSON Schema Validator

Validate JSON data against a JSON Schema. Paste your schema on the left and data on the right - get instant pass/fail with detailed error messages showing exactly which property failed and why.

FAQ

JSON Schema is a vocabulary that lets you annotate and validate JSON documents. You define what properties an object must have, what types they should be, and constraints like min/max values, patterns, and required fields. It's the standard way to document and validate API payloads.

This tool covers the most commonly used keywords: type, properties, required, items, pattern, minimum/maximum, minLength/maxLength, minItems/maxItems, and enum. For full draft-2020-12 support, consider a dedicated library like Ajv.

API definition (OpenAPI/Swagger uses JSON Schema subset), configuration file validation, form validation, automated testing of API responses, and IDE autocomplete for JSON files. It's a standard across REST APIs, Kubernetes, and many other systems.

The validator supports JSON Schema Draft-07 and Draft 2020-12, the most widely adopted versions. It checks required properties, type matching, pattern validation (regex), enum values, minimum/maximum numeric constraints, and nested object/array schemas.

No. All validation runs entirely in your browser using JavaScript. Your schema and data never leave your machine - it's safe for sensitive payloads and proprietary API schemas.