Purpose: This paper aims to identify and discuss factors affecting students' performance in web-based learning (WBL) during the COVID-19 pandemic. Design/methodology/approach: This study uses a quantitative method to analyze data collected using an online structured questionnaire. Responses were gathered from undergraduate students (n = 270) studying engineering education at a university in Indonesia. A measurement analysis is used to validate the instruments, and structural equation modeling is used to examine the associations among constructs. Findings: Attitude, anxiety and motivation affected students' performance in WBL. Motivation played an essential role in influencing WBL. The results also showed equal opportunities between men and women in WBL. Research limitations/implications: This research may provide a foundation for future research designing WBL in higher education. This study provides valuable insights in policy formulation and an effective web-based e-learning design by considering students' personal characteristics potentially affecting WBL performance. Originality/value: This study identifies factors influencing students' performance in WBL. Furthermore, it added students' genders to explore the moderating effect on the model.