JSON to TypeScript

Generate TypeScript interfaces from a JSON sample, inferring types recursively.

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About this tool

Paste a JSON sample and get matching TypeScript interfaces, generated entirely in your browser.

How are nested objects handled?

Each nested object becomes its own interface, named in PascalCase after its key, with a Root interface on top.

How are arrays typed?

Arrays are typed from their first element as T[]; empty arrays become any[].