This study develops a comprehensive scale for measuring customers' mental imagery for commercial web sites. Following Churchill's framework, a number of methodological instruments including two focus groups (the first with 4 experts and the second with 9 PhD students) and three surveys (151 students for the first survey, 205 and 200 web surfers, respectively, for the second and the third surveys) are used. The confirmatory factor analysis (CFA) resulted in a multiple‐item (13 items) scale with four dimensions; quantity/ease, links, vividness/clarity and valence, which seems to exhibit evidence of reliability and validity.