JSON to TypeScript

Generate TypeScript interfaces from JSON. Stop writing types by hand.

Installation

npm install -g @lxgicstudios/json-to-ts

Commands

From File

npx @lxgicstudios/json-to-ts data.json
npx @lxgicstudios/json-to-ts response.json -n User

From URL

npx @lxgicstudios/json-to-ts https://api.example.com/users -n User

From Pipe

curl https://api.example.com/data | npx @lxgicstudios/json-to-ts -n ApiResponse

Output to File

npx @lxgicstudios/json-to-ts api.json -o src/types/api.ts

Example

Input JSON:

{
  "id": 1,
  "name": "John",
  "email": "john@example.com",
  "address": { "city": "NYC" },
  "tags": ["dev", "ts"]
}

Output:

export interface Address {
  city: string;
}

export interface Root {
  id: number;
  name: string;
  email: string;
  address: Address;
  tags: string[];
}

Options

Features

• Nested objects become separate interfaces
• Arrays properly typed
• Mixed arrays become union types
• Fetches directly from URLs
• Handles empty arrays as unknown[]

Common Use Cases

Type an API response:

curl https://api.github.com/users/octocat | npx @lxgicstudios/json-to-ts -n GitHubUser

Generate types for project:

npx @lxgicstudios/json-to-ts sample-response.json -o src/types/api.ts -n ApiResponse

Built by LXGIC Studios

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