How are arrays of objects typed?

All items are merged into a single interface. A field absent from some items becomes optional (marked with ?).

Are nested objects given their own interfaces?

Yes — every nested object gets a named, exported interface derived from its key, so the output drops straight into your codebase.

JSON to TypeScript Interfaces

Paste a payload, get ready-to-use TypeScript types.

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input.jsonpaste, drop a file, or load the sample

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The view appears once there is JSON to show.

Types from real payloads

Hand-writing interfaces for a big API response is busywork. Paste the JSON and get exported interfaces for every nested object. Array items are merged into one element type — fields missing from some items are marked optional with ?.

Everything runs in your browser — your JSON never leaves your device, so it is safe for API keys, customer records, and production payloads.

Frequently asked questions

How are arrays of objects typed?: All items are merged into a single interface. A field absent from some items becomes optional (marked with ?).
Are nested objects given their own interfaces?: Yes — every nested object gets a named, exported interface derived from its key, so the output drops straight into your codebase.