Chronotype predicts university students' expected and actual grades above conscientiousness and intelligence

Many factors contribute to academic achievement. Among the well-established predictors of educational outcomes are intelligence and conscientiousness. In the current study, we explored the role of another characteristic, chronotype (i.e., individual differences in the timing of sleep and activity during a 24-h day), in predicting university students' grade point average (GPA). In the current research (N = 273), we investigated the association between chronotype and both the expected GPA estimated by students a few weeks before the exam session and their actual GPA. Additionally, we included intelligence and conscientiousness to assess their combined influence with chronotype on academic performance. In line with our hypotheses, evening-oriented students exhibited lower expected and actual GPAs. Furthermore, chronotype predicted GPA (both expected and actual) beyond intelligence and conscientiousness. Lastly, evening-oriented students demonstrated a relatively accurate ability to estimate their GPA two weeks before the exams. Our findings highlight the significant role of chronotype in academic performance, especially given that the university system is typically organized in a manner that favors morning-oriented individuals.