JSON to TypeScript Interface Converter

Paste any JSON and get back TypeScript interface declarations, inferred entirely in your browser. Arrays of objects are structurally merged: a field present in every sample stays required, a field missing from some samples becomes optional (?), and a field whose value type varies becomes a union (e.g. string | number). Repeated nested shapes (like two differently-named address objects with the same fields) are deduplicated into a single shared interface.