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JSON to Python Class
Convert JSON to Python dataclasses, Pydantic models or TypedDicts with type hints and Optional fields.
Runs in your browser. Your data never leaves your device.
How to use the JSON to Python Class
- Paste a sample JSON.
- Choose dataclass, Pydantic or TypedDict.
- Copy the Python code.
About this tool
Generate typed Python models from JSON: standard dataclasses, Pydantic models for FastAPI, or TypedDicts. Keys become snake_case attributes, nested objects become their own classes and missing values become Optional.
Frequently asked questions
Which style should I use?
Pydantic validates data at runtime and suits FastAPI. Dataclasses need no extra package. TypedDict only adds type hints to plain dicts.
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