Proper error handling separates professional APIs from amateur ones. This FastAPI tutorial demonstrates how to return meaningful HTTP status codes like 201 for creation and 404 for missing resources.

The framework automatically provides validation errors with 422 codes when data fails Pydantic checks. Developers must explicitly set appropriate status codes rather than relying on FastAPI's defaults.

Custom HTTPException handling allows detailed error messages including suggestions for users. Advanced developers can create custom exception handlers for consistent API-wide error responses across their applications.