JSON to TypeScript Converter
Convert JSON into clean TypeScript interfaces or type definitions instantly. 100% private in browser.
JSON Input
TypeScript Output
How to Convert JSON to TypeScript
Paste JSON
Paste your raw JSON payload from an API response, database query, or JSON file.
Instant Type Generation
ToolJi automatically parses JSON and generates strongly-typed TypeScript interfaces in real time.
Copy or Download
Copy the generated code to your clipboard or download a .ts file for your React or Next.js app.
JSON to TypeScript Examples
{
"id": 1,
"name": "John",
"address": {
"city": "Delhi"
}
}export interface Address {
city: string;
}
export interface Root {
id: number;
name: string;
address: Address;
}Frequently Asked Questions
What is a JSON to TypeScript Converter?
A JSON to TypeScript converter automatically analyzes any raw JSON data structure and generates clean, strongly-typed TypeScript interfaces or type aliases. It recursively extracts nested objects into separate interfaces, handles arrays of objects, and formats invalid property keys.
How does the tool handle nested objects?
When your JSON contains nested object structures (like an address object inside a user object), ToolJi automatically generates separate, reusable child interfaces (e.g., interface Address and interface User) for clean type organization.
How are inconsistent object arrays handled?
If an array contains objects with varying properties, ToolJi merges all keys across all array items. Any property that does not appear in every object is automatically marked as optional with the ? modifier.
Is my JSON uploaded to any server?
No! 100% of the JSON parsing and TypeScript type generation happens locally inside your web browser. Your JSON data is never sent to a server or stored remotely.
Can I download the generated TypeScript types?
Yes! You can copy the generated code with 1-click or download it as a ready-to-use generated-types.ts file.