JSON to TypeScript — Generate TypeScript Interface from JSON
Automatically generate TypeScript interfaces from any JSON structure. Handles nested objects, arrays, and multiple types. Copy the output directly into your TypeScript project. 100% client-side — your data stays private.
How to Use the JSON to TypeScript Converter
- Paste a JSON object or array in the left panel.
- Set the root interface name in the header (default:
RootObject). - Click "Generate" to create TypeScript interfaces for all nested structures.
- Copy the output and paste it into your
.tsfile. - Nested objects get their own interfaces, and arrays of objects generate item interfaces.
Why Use This JSON to TypeScript Converter
When building TypeScript applications that consume JSON APIs, you need interfaces that match the API response shape. Manually writing interfaces for complex nested structures is tedious and prone to errors.
This tool automatically generates accurate TypeScript interfaces from any JSON
structure. It handles nested objects (creating separate interfaces for each), arrays (generating
typed arrays), and infers primitive types like string, number, and boolean.
Frequently Asked Questions
Each nested object gets its own interface with a name derived from its property key. For example, an address property with nested fields generates an IAddress interface. The root object uses the name you specify in the header.
If an array contains objects, the tool generates an interface for the array item type and types the property as IItem[]. If an array contains primitives, the property is typed as string[], number[], etc.
The generated interfaces use standard TypeScript syntax compatible with TypeScript 2.x and above. They use the interface keyword and follow conventional I prefix naming.
Use Cases
API Client Generation
Generate typed interfaces for REST API responses to use with fetch or axios calls.
Config Type Safety
Create interfaces for JSON config files so your IDE catches type errors at compile time.
Rapid Prototyping
Quickly scaffold TypeScript types from sample JSON when starting a new project.
Migration to TypeScript
Convert existing JavaScript projects by generating interfaces for all JSON data structures.