Developer Tools
JSON to TypeScript
Generate readable TypeScript interfaces from a JSON example in one click.
TypeScript definitions
How to use
Convert a representative JSON payload into TypeScript interfaces for API clients, application models, and quick prototypes.
- Paste a valid JSON object, array, or primitive sample.
- Choose the root type name for the generated definitions.
- Generate and copy the inferred TypeScript interfaces.
Best for
- API client models
- Frontend prototypes
- Typed test fixtures
Why the result matters
- Generated types reflect the supplied example, so use a representative payload with all important fields.
- Empty arrays become unknown arrays because there is no sample item from which to infer a type.
Example inputs
- Generate interfaces from an API response
- Create a RootObject type for fixture data
- Infer nested object and array types
FAQ
Does this generate a complete JSON schema?
No. It infers TypeScript definitions from the current example rather than building a full schema.
How are nested objects handled?
Nested objects are generated as named interfaces and referenced by their parent fields.
What happens with mixed arrays?
The generator creates a union of the distinct member types found in the sample array.
Is the JSON sent anywhere?
No. Type inference happens entirely in the browser.