JSON to Type Definitions Generator

Why Type Generation Matters

Consuming dynamic REST or GraphQL API endpoints without static typing creates brittle runtime failures in production applications. Manually writing boilerplate data transfer objects (DTOs), serialization tags, and nested structs is slow and error-prone.

This generator infers structural schemas directly from representative JSON payloads: distinguishing between 64-bit floating point numbers and integers, analyzing nested objects and homogeneous arrays, mapping snake_case keys to idiomatic PascalCase fields, and outputting production-ready type definitions.

Supported Target Languages

• TypeScript: Generates clean interface definitions with proper object nesting, array type arrays, and primitive typings.
• Go: Generates type ... struct blocks with idiomatic PascalCase field names and explicit `json:"key"` struct tags.
• Python (Pydantic v2): Emits BaseModel definitions with Field(..., alias="key") annotations, supporting Python's standard type hints (List, Optional).
• Rust (Serde): Produces pub struct declarations equipped with #[derive(Serialize, Deserialize)] and #[serde(rename = "...")] attributes.
• JSON Schema: Exports Draft-07 compliant schema definitions complete with property typings and required field arrays.

Frequently Asked Questions

How does the converter handle arrays of objects?

When an array of objects is encountered, the generator inspects the structure of the elements, synthesizes an independent sub-interface (e.g. UserItem or OrderItem), and binds the parent field as an array of that type.

Can I change the root model or interface name?

Yes. Simply edit the "Root Name" field in the top toolbar to rename the primary entrypoint model.

Is any JSON data transmitted to third parties?

No. All parsing, tree traversal, and code synthesis happens 100% locally in your browser memory.