Purpose: The purpose of this study was to determine the impact of perceived usability and students' personality traits on their learning gain in an e-learning context at the university level. Design/methodology/approach: The factors examined are related to individual characteristics such as students' personality traits, as well as to perceptual characteristics such as the perceived usability of the platform used. A total of 110 undergraduate students participated in the study. A one-group pretest-posttest research design was adopted. Big 5 personality test, System Usability Scale (SUS) and a general knowledge assessment questionnaire were used. Findings: Perceived usability of Zoom platform is statistically significantly correlated with students' learning gain (r = 0.294, p = 0.002, s). Concerning learning effectiveness in the current e-learning scenario, students' final performance was found to be statistically significantly higher than the initial (p = 0.000, s). A hierarchical regression analysis (R[superscript 2] = 0.146) unveiled that Zoom's perceived usability and personality traits are significant predictors for learning gain (p = 0.011, s). Research limitations/implications: The findings of this research provide important implications regarding the design of lessons in an e-learning context. Social implications: A substantial fraction of the educational process is going online, especially in higher education. Thus, a thorough understanding of the factors which influence learning gain in an e-learning context is of significance. Originality/value: The main contribution of this study is that it quantifies the variance of the learning gain explained by two factors, namely, SUS and personality.