With the development of technology, there are advances that help civilizations on their day-to-day activities, one of which is the implementation of e-Learning on the Final Exams. A standardized national computer-based final examination in Indonesia is called Ujian Nasional Berbasis Komputer (UNBK). Despite the fact that UNBK has been held nationwide since 2016, its interface and system have only gone through minor improvement throughout the years. To improve the usability and interface of UNBK, it is necessary to first evaluate the current interface from the users. The user evaluation was conducted using a mixed-method approach to compare and/or relate qualitative data and quantitative data. The user evaluation using an online questionnaire with the Post-Study System Usability Questionnaire (PSSUQ) shows that UNBK's quality only exceeds in System Quality with a score of 75.71 out of 100. The online questionnaire data is supported with the qualitative data of contextual interviews, resulting in an affinity diagram to observe users' needs, pain points, and missing opportunities. The improved interface design according to the users' feedbacks was also tested using Usability Testing. The result of the UT shows that it has the binary task succession rate of 86.50%.