Perceived fit of students is one of the most prominent predictors of study success in higher education, but when assessed directly, it provides lots of room for interpretation for the respondents. This is also true for perceived demands-abilities fit (e.g. how do one's abilities fit with study demands), which has particularly high associations with study success. We, therefore, investigated (1) how students combine demands and abilities when asked about their perceived demands-abilities fit and (2) which demands and abilities they have in mind when asked about their perceptions of fit in an unspecific manner. We obtained data on the perceived fit of N = 595 university students from four German-speaking countries and analyzed them using response surface analysis. The results indicate that (1) perceived demands-abilities fit does not correspond to the congruence of perceived demands and perceived abilities when the latter two are measured separately, but rather reflects a strong linear effect of the abilities. Furthermore, they show that (2) the specific demands and abilities do not influence the way how demands and abilities are combined to a fit score, but that there are differences in the amount of explained variance between the specific demands and abilities. The results speak for a new interpretation of prior findings and challenge the contemporary understanding of perceived fit. For example, perceived fit and self-efficacy might be more closely associated than previously assumed. When striving to enhance perceived fit, practitioners should thus focus on fostering individual abilities and their perceptions.