Metacognitive judgment of one's online search process (calibration) is an important element of searching efficiency. This study investigated Chinese university students' calibration during online information search. Fourteen students s were asked to search answers for three assigned tasks. Immediately after the search, all participants attended individual interviews about their search behavior. Based on eye-tracking data of the actual search process, three profiles of searchers were identified: surface explorers, deep explorers, and smooth searchers. Eye-tracking and retrospective interview data were analyzed to examine the participants' level of calibration. Results showed that the participants were not able to calibrate well on their searching process, with a mean score of 3.64 out of 10.0 (SD = 1.91), suggesting a mediocre level of calibration capacity. A moderate level of positive relationship (r = 0.42, p > 0.05) was also found between calibration scores and search performance scores, implying a general pattern wherein the high calibration group tended to perform better than the low calibration group. The findings called for integrating metacognitive judgment as a component of improving computer information literacy which, accordingly, could be used to enhance students' ability to think critically about seeking and evaluating information.