Abstract

This study examines the balance between usability and security in electronic online services by comparing the effectiveness and user experience of different authentication methods, including password-only authentication, multi-factor authentication (MFA), and biometric authentication. A mixedmethods approach was used to collect both quantitative and qualitative data through usability tests, surveys, semi-structured interviews, and case studies. The findings reveal a clear trade-off between usability and security. While MFA offers stronger protection, it poses usability challenges, especially for novice users who face more errors and take longer to complete tasks. In contrast, password-only authentication was faster and easier, but was seen as inadequate for protecting sensitive data. Biometric authentication emerged as the most preferred option, receiving high satisfaction ratings from both novice and experienced users due to its balance between ease of use and security. These results emphasize the importance of designing usercentered security solutions, such as increasing the adoption of biometric methods and simplifying MFA to enhance the user experience without sacrificing security. The study offers practical recommendations for developers and security professionals to create more accessible and secure online services.