JSON to TypeScript Converter — Free & Instant

Paste any JSON and get clean, ready-to-use TypeScript interfaces in one click. Nested objects, arrays and union types handled automatically — identical structures deduplicated into a single interface.

Convert JSON to TypeScript →
🔒 100% private — runs in your browser ⚡ Instant — no upload 🌟 Free — no signup, no ads

Example

Input JSON
{
  "id": 1042,
  "name": "Anjan",
  "active": true,
  "tags": ["dev", "k8s"],
  "owner": {
    "email": "[email protected]"
  }
}
Generated TypeScript
interface Owner {
  email: string;
}

interface Root {
  id: number;
  name: string;
  active: boolean;
  tags: string[];
  owner: Owner;
}

How to convert JSON to TypeScript

1
Open the JSON Formatter and paste your JSON — it validates and formats automatically.
2
Click JSON → TS in the toolbar.
3
Copy or download the generated interfaces straight into your project.

Why type your API responses?

Hand-writing interfaces for large API payloads is slow and error-prone. Generating them from a real response gives you accurate types in seconds — autocomplete, compile-time safety and refactoring support with zero guesswork. If your JSON is broken (single quotes, trailing commas, Python literals), the built-in Fix & Analyze repairs it first, so even messy log output converts cleanly.

FAQ

Does it handle nested objects and arrays?

Yes — nested objects become their own interfaces, arrays are typed as T[], and mixed-type arrays become union types like (string | number)[].

Is my JSON uploaded anywhere?

No. Everything runs in your browser. Nothing is sent to any server.

What about duplicate structures?

Structurally identical objects are deduplicated — an array of 100 identical items produces one interface, referenced as Item[].

Is it free?

Completely free, no signup, no ads, no limits.

Try it now — free →