The first aim of this study was to test the self‐consistency model (SCM) of subjective confidence as it applies to personal preferences. According to SCM, participants presented with a two‐alternative forced‐choice (2AFC) item draw a small sample of representations of the item. Their confidence reflects the extent to which the choice is representative of the population of representations associated with the item, and the likelihood of making that choice on subsequent occasions. The second aim was to use confidence judgment as a clue to the dynamics of online preference construction. Participants were presented with 2AFC items measuring everyday personal preferences. The task was presented five times. In line with SCM, (i) when participants changed their preferences across presentations, they were systematically more confident when they made their more frequent choice; (ii) confidence in a choice in the item's first presentation predicted the likelihood of repeating that choice in subsequent presentations; (iii) despite the idiosyncratic nature of personal preferences, confidence was higher for consensual than for nonconsensual preferences; (iv) when participants predicted the preferences of others, they were also more confident when their predictions agreed with those of others; and (v) the confidence/accuracy correlation for predictions was positive for consensually correct but negative for consensually wrong predictions. These results suggest that confidence in preferences can help separate between the stable and variable contributions to preference construction in terms of the population of representations available in memory and the representations that are accessible at the time of preference solicitation, respectively. Copyright © 2012 John Wiley & Sons, Ltd.