What happens when an array has mixed types?

The parser inspects all items in the array and constructs a union type, such as (string | number)[].

Can I use this generated code in strict TypeScript projects?

Yes, the generated types adhere strictly to modern TypeScript compiler standards with no implicit any types where possible.

Quick Switch

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JSON to TypeScript Converter

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Convert JSON objects into TypeScript interfaces.

100% In-Browser Execution

Root Name:

exportoptional (?)

JSON Input

500 chars

{
  "id": "usr_9124",
  "username": "alex_dev",
  "email": "alex@adyve.com",
  "isVerified": true,
  "karma": 1540,
  "roles": [
    "admin",
    "developer"
  ],
  "profile": {
    "bio": "Full-stack engineer building fast developer tools.",
    "website": "https://adyve.com",
    "socials": {
      "github": "https://github.com/adyve",
      "twitter": "https://twitter.com/adyve"
    }
  },
  "settings": {
    "theme": "dark",
    "notificationsEnabled": true,
    "emailDigest": "weekly"
  }
}

Generated TypeScript

// Click 'Generate TypeScript' above

Tool Documentation, Shortcuts & FAQs

How to Use JSON to TypeScript Converter

1Paste your sample JSON payload into the input editor.
2Enter the desired Root Interface name (e.g., 'RootObject' or 'ApiResponse').
3Toggle between 'interface' and 'type' syntax if preferred.
4Click 'Convert to TypeScript'.
5Copy or download the generated TypeScript (.ts) definition.

Key Capabilities

Interface & Type Alias Modes

Generate either standard 'interface' declarations or TypeScript 'type' aliases.

Deep Nested Object Extraction

Automatically factors out nested objects into distinct, reusable child interfaces.

Smart Array & Union Inference

Infers array element types, including union types like (string | number)[] when arrays contain mixed primitives.

Configurable Root Name

Customize the root interface name (e.g. 'ApiResponse', 'UserProfile', 'ConfigSettings').

Frequently Asked Questions

Nested objects are recursively extracted into PascalCase child interfaces named according to their property key to ensure clean, modular code.

Zero Data Retention

All calculations are performed strictly in client-side memory using your browser engine. No data is ever sent across the network.

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