This short paper presents initial results from a project, in which we investigated differences in how users view relevant and irrelevant Web pages on their visits and revisits. The users’ viewing of Web pages was characterized by eye-tracking measures, with a particular attention paid to changes in pupil size. The data was collected in a lab-based experiment, in which users (N=32) conducted assigned information search tasks on Wikipedia. We performed non-parametric tests of significance as well as classification. Our findings demonstrate differences in eye-tracking measures on visits and revisits to relevant and irrelevant pages and thus indicate a feasibility of predicting perceived Web document relevance from eye-tracking data. In particular, relative changes in pupil size differed significantly in almost all conditions. Our work extends results from previous studies to more realistic search scenarios and to Web page visits and revisits.