A particular concern in Danish higher education policy is how much time students spend studying, often addressed as ‘study intensity’ (defined as number of hours per week spent studying). This article discusses this concept and explores how students perceive the time they spend studying. We draw on ethnographic fieldwork, interviews and workshops among second-year students at four study programmes at a Danish research-intensive university: two in natural sciences, one in humanities, and one in social sciences. We found that students live their lives across different realms where only some relate to their university studies. The students continuously balanced their time between different activities and requirements. While students studied following time schedules, they also expressed a qualitative perception of time, for example, distinguishing between the work effort and the mental effort they put into studying. Spending time on study activities therefore does not necessarily mean investing mental, qualitative time. The emphasis on ‘study intensity’, and time as quantity in higher education policy and in student-engagement surveys fails to capture what drives students’ study practices, and policy measures run the risk of being detrimental to the study quality.