Home / Tools / JSON to TypeScript
JSON to TypeScript
Generate TypeScript types from JSON
Features
Automatic Type Generation
Paste JSON to generate corresponding TypeScript interface or type definitions, covering strings, numbers, booleans, null, arrays and nested objects.
Nested Object Splitting
Nested objects are split into independently named interfaces with type-safe field references for clean, maintainable structures.
Smart Array Inference
Homogeneous arrays infer to single-element arrays (Item[]), while heterogeneous arrays generate union types ((string | number)[]).
Custom Names & Styles
Customize the root interface name and switch between interface/type output styles to match your project conventions.
How to Use
Step 1: Paste JSON
Paste JSON data into the input area, or click "Load Sample" to try it instantly.
Step 2: Configure options
Set a custom root type name (default RootObject) and choose interface or type output style.
Step 3: Generate and copy
Click "Generate Types" to get TypeScript definitions, then "Copy Result" to paste into your .ts file.
常见问题
Is the JSON to TypeScript tool free?
Yes, completely free with no registration or usage limits.
Will my data be sent to a server?
No. Parsing and type generation happen locally in your browser. Your data never leaves your device.
What if array elements have different types?
The tool automatically generates a union type array, e.g. [1, "a", true] becomes (number | string | boolean)[], covering all element types.
Which JSON value types are supported?
string, number, boolean, null, arrays, nested objects and empty objects (Record<string, unknown>) — the full JSON spec.
仍有疑问？欢迎访问 AI Developer Toolbox 首页查看更多工具。
More Tools
Explore other free online developer tools