# Register using API

User registration with Passkeys is split into 2 functions / API requests [initiate-registration](https://docs.0xpass.io/authentication/passkeys/registration/register-using-api/initiate-registration "mention") and [complete-registration](https://docs.0xpass.io/authentication/passkeys/registration/register-using-api/complete-registration "mention").

The `initiateRegistration` method initiates the user registration process within a specific scope. It generates a registration challenge that the user must solve to proceed with their registration which occurs in `completeRegistration`. 

The `completeRegistration` method is the part of the authentication API that finalizes the user registration process. It takes encrypted user data and a registration challenge, verifies it, and if successful, returns an identifier for the user.