The Passkey Promise: A Comparative Usability Study of MFA Methods

Passkeys, the latest evolution of FIDO2 credentials, promise to combine enhanced security with improved usability. While passkeys are widely promoted as the long-awaited replacement for passwords, their real-world usability remains underexplored - particularly as a passwordless and usernameless Multi-Factor Authentication (MFA) method in complex, heterogeneous environments like universities. Addressing this gap, we conducted a between-groups lab study with 92 university participants, comparing passkeys against security keys and one-time passwords across students, faculty, and staff. Our results show that passkeys are perceived as the most usable and accepted MFA method while enabling faster authentication. However, we also identified critical barriers including personal device requirements, exam scenario conflicts, privacy concerns, and recovery fears. These findings suggest that while passkeys outperform traditional MFA methods, successful deployment in academic settings requires addressing institutional constraints and providing role-specific implementation strategies.