JSON to OpenAPI schema
Generate an OpenAPI component schema from sample JSON in one click.
Objects and arrays are mapped to JSON Schema with required fields, and mixed arrays become oneOf definitions.
Everything runs locally in your browser—no data is sent anywhere.
JSON to OpenAPI Schema Generator
Instantly infer and generate OpenAPI (Swagger) 3.x components.schemas YAML/JSON definitions by simply pasting an exogenous API response or a design-phase dummy JSON object.
During REST API development or technical documentation authoring, manually mapping out massive JSON properties and dictating types is a tedious, error-prone task. This structural inference tool automates the heavy lifting of reverse-engineering your API schema, accelerating your documentation process.
Articles for this tool
Create OpenAPI (Swagger) Schemas from JSON
OpenAPI 3.0 is the standard for API documentation. Learn how to efficiently generate schemas from existing JSON to accelerate your documentation process.
Mastering the JSON Ecosystem: Best Practices for Type Safety and Schema Management
JSON is more than just a data format; it's the backbone of modern development. From TypeScript types and Zod validation to OpenAPI documentation, learn how to leverage the modern JSON ecosystem.
JSON Formatting and Validation: How to Read API Responses Safely
Learn how to format JSON, catch syntax errors, inspect value types, and turn API responses into types, schemas, or documentation.
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