JSON to Schema Generator
Generate JSON Schema from sample JSON data
Schema will appear here...
About JSON to Schema Generator
Generate JSON Schema from sample JSON data automatically. Paste any JSON object or array and get a valid JSON Schema definition with types, required fields, and nested structures. Perfect for building API validators, OpenAI function calling definitions, and Anthropic tool use schemas. Supports Draft 2020-12 output.
Use Cases
- Creating schemas for OpenAI function calling / tool use
- Generating Anthropic tool input schemas from example data
- Building API request/response validators
- Documenting API payload structures automatically
Frequently Asked Questions
What is JSON Schema?
JSON Schema is a declarative format for describing the structure of JSON data. It defines types, required properties, nested objects, arrays, and constraints — commonly used for API validation and documentation.
Can I use this for OpenAI function calling?
Yes! The generated schema follows the JSON Schema standard which is exactly what OpenAI expects for function parameter definitions and Anthropic expects for tool input schemas.
Does it handle nested objects and arrays?
Absolutely. The generator recursively processes any depth of nesting, generating proper schema definitions for objects within objects, arrays of objects, and mixed-type arrays.
Is my data processed locally?
Yes. The schema is generated entirely in your browser. Your JSON data never leaves your device.