What is OpenAPI to TypeScript SDK Generator?
This tool converts OpenAPI 3.0/3.1 and Swagger 2.0 specifications into a fully typed TypeScript SDK using the native fetch API. It generates TypeScript interfaces for all schemas and a client class with typed methods for each endpoint, with zero external dependencies.
How to Use
- Set the SDK client class name (default: ApiClient)
- Paste your OpenAPI or Swagger specification (JSON or YAML format)
- Click "Generate SDK" to create the TypeScript code
- Copy the generated files (types.ts, sdk.ts, index.ts) to your project
Why Use This Tool?
Tips & Best Practices
- The generated SDK works in both browser and Node.js 18+ environments
- Use the operationId field in your spec for cleaner method names
- You can extend the generated class to add authentication logic
- The SDK includes helper methods to update baseUrl and headers at runtime
Frequently Asked Questions
What OpenAPI versions are supported?
OpenAPI 3.0.x, 3.1.x, and Swagger 2.0 specifications are all supported. The tool automatically detects the version and handles the differences.
Why use fetch instead of axios?
Fetch is a native web standard available in all modern browsers and Node.js 18+. It requires no dependencies, resulting in smaller bundle sizes and simpler deployment.
How are $ref references handled?
All $ref references are resolved and converted to TypeScript type references. Schemas from components/schemas (OpenAPI 3.x) or definitions (Swagger 2.x) are generated as interfaces.
How do I use the generated SDK?
Import the client class, create an instance with your base URL, and call the typed methods. Example: const api = new ApiClient({ baseUrl: "https://api.example.com" }); const pets = await api.listPets();
Can I add authentication?
Yes! Pass headers in the config: new ApiClient({ baseUrl: "...", headers: { Authorization: "Bearer token" } }). You can also call setHeaders() to update headers at runtime.