JSON to TypeScript

Paste any JSON and instantly generate a matching TypeScript interface, including nested objects and arrays.

Root interface name

JSON input

Generated TypeScript

interface Address { city: string; zip: string; } interface Root { id: number; name: string; active: boolean; tags: string[]; address: Address; }

About the JSON to TypeScript

This tool converts a JSON object into a matching TypeScript interface, inferring the correct type for every field including nested objects and arrays, so you don't have to type it out by hand.

How to use

Paste a sample JSON object into the input field.

Optionally set a name for the root interface.

Copy the generated TypeScript interfaces into your project.

Frequently asked questions

Does this generate types for nested objects too?

Yes, any nested object gets its own named interface, generated automatically based on the key it was found under.

What happens if a field could be null?

A field with a null value in your sample JSON is typed as null. If that field could also hold other values elsewhere, you may want to manually adjust the type to a union afterward.

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