JSON to TypeScript
Infer TypeScript interfaces from a JSON sample. Nested objects become named interfaces, and keys missing from some objects in an array are optional. Conversion stays in the tab.
Runs in your browser. Nothing is uploaded.
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About this tool
Infer TypeScript from a JSON sample. Objects become named interfaces. Keys missing from some objects in an array are optional. Values that disagree become a union, including null.
How to use: paste JSON, copy the interfaces. A root array of objects is exported as type Root. Empty objects become Record<string, unknown> and empty arrays become unknown[]. This is a starting point, not enums, generics, or a JSON Schema compiler.
Example: {"id":1,"name":"Ada","address":{"city":"London"}} yields interface Root and interface Address. Related: JSON to JSON Schema for a schema draft, JSON to Code for JS, Python, or PHP literals.
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