JSON Schema Generator

The JSON Schema Generator automatically infers a JSON Schema (Draft-7) from any sample JSON object. Instead of writing schemas by hand, simply paste a representative JSON document and get a complete, validated schema in seconds.

What is JSON Schema?

JSON Schema is a vocabulary that allows you to annotate and validate JSON documents. It describes the structure, data types, and constraints of your JSON data. Draft-7 is one of the most widely supported versions and is used by tools like Ajv, Postman, and many API gateways.

How the inference works

• null values become {"type": "null"}
• Integers (whole numbers) use type: integer
• Decimals use type: number
• Arrays infer their item schema from the first element
• Objects recursively infer all nested properties
• All keys can be marked as required automatically

Common use cases

• Validating API request/response payloads
• Generating TypeScript types from JSON data
• Building form validation schemas
• Documenting data structures for OpenAPI/Swagger specs