A method, a system, and a non-transitory computer readable program code are disclosed for authenticating users for services. The method includes registering one or more users in an authentication system; assigning a score index to each of the one or more users in the authentication system for one or more services, the score index representing a security level and corresponding authentication required to access each of the one or more services; inputting each request for services from the one or more users into the authentication system to continuously update the score index for each of the one or more users, each of the requests including one or more authenticators or biometric identifiers for the requested service; and requesting the one or more users to register one or more additional authenticators or biometric identifiers with the authentication system upon the score index for a user reaching of a predefined threshold value.