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JSON to TypedDict

Convert JSON into Python TypedDict classes for type checking dicts. Required and optional keys are split into total and non-total classes.

JSON input

Paste JSON, optionally name the root type, then generate.

Your Python TypedDict code will appear here.
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Types for the dicts you already have

Not every codebase wants to convert JSON into objects. TypedDict gives you static checking over plain dicts: the generator creates one class per object level and splits reliably present keys from sometimes missing ones using total=False.

Catch key errors before runtime

A typo like data['nmae'] fails silently at runtime until that line executes. With the generated TypedDict, mypy and modern editors flag it the moment you type it, which is invaluable in large data pipelines.

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JSON to TypedDict FAQs

What is a TypedDict?
TypedDict lets type checkers like mypy verify the keys and value types of a plain dict. It adds static typing without changing your runtime code at all.
How are optional keys handled?
Keys missing from some records go into a subclass declared with total=False, while always present keys stay in the main class. This matches how mypy expects partial dicts to be modeled.
When should I use TypedDict over a dataclass?
Use TypedDict when your code already passes dicts around, for example parsed JSON you do not want to convert. Use dataclasses when you want real objects with methods.
Does this change runtime behavior?
No. TypedDict is typing only; at runtime the values remain ordinary dicts. The benefit is editor autocomplete and mypy catching wrong key access.
Can nested dicts be typed?
Yes. Each nested object becomes its own TypedDict class, so deep key access like data['address']['city'] is fully type checked.
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