How does it handle nested objects and arrays?

Nested objects generate their own separate interfaces, and arrays are typed based on their element type, producing properly structured, nested TypeScript types.

What if a field's value type varies across array items?

It infers a reasonable type from the sample provided — for genuinely mixed types, you may want to refine the generated interface manually afterward.

Does it generate interfaces or types?

It generates TypeScript interfaces, the standard convention for describing object shapes.

Does JSON to TypeScript upload my files to a server?

No. JSON to TypeScript runs entirely in your browser using on-device processing, your files never leave your device.

JSON to TypeScript

Generate TypeScript interfaces from a sample JSON object.

Runs in your browser

JSON input

Root interface name

About this tool

Writing TypeScript interfaces by hand to match a JSON API response's shape is tedious and easy to get subtly wrong, especially for a response with nested objects and arrays. This tool generates TypeScript interfaces directly from a sample JSON object, giving you accurate starting types instead of hand-transcribing the shape of a JSON response.

Frequently asked questions

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