JSON to Python
Paste JSON and get typed Python classes — either @dataclass definitions or Pydantic BaseModels. Nested objects become their own classes, and optional fields become Optional[...] with a None default. Everything runs locally in your browser.
Frequently asked questions
Does my JSON get uploaded?
No. Classes are generated entirely in your browser — nothing is sent to a server.
Dataclass or Pydantic — which should I pick?
Use @dataclass for plain, dependency-free models. Choose Pydantic when you want runtime validation and parsing (e.g. in FastAPI).
How are optional fields handled?
Fields that are missing or null in some records become Optional[...] and are ordered after required fields with a None default so the class stays valid.