Does it handle nested objects?

Yes. Nested objects are extracted into separate named interfaces. The root interface references them by name.

What TypeScript types are generated?

string, number, boolean, null, named interfaces for objects, and typed arrays (e.g. string[]).

Can I use this for API response types?

Yes. Paste a sample API response and the tool generates interfaces that match the response shape. You may need to add optional (?) markers for fields that can be absent.

JSON to TypeScript

Paste a JSON object and get TypeScript interface definitions generated automatically. Handles nested objects, arrays, and all primitive types.

Runs entirely in your browser — your input is never uploaded, stored, or logged.

Generated interfaces give you type safety when consuming API responses or working with JSON data in TypeScript projects. For Python, see JSON to Python.

How to Use

1Paste your JSON into the input box.
2Set the root interface name (default: Root).
3Click Generate TypeScript.
4Copy the generated interfaces or download as a .ts file.

Common Uses

→Generate TypeScript interfaces from an API response to add type safety
→Convert JSON configuration files to typed interfaces
→Scaffold types when starting a new TypeScript project with existing data
→Type-check data structures without writing interfaces by hand

Examples

Simple object

Input

{"name":"Alice","age":29,"active":true}

Output

interface Root {
  name: string;
  age: number;
  active: boolean;
}

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