How do people monitor their knowledge during acquisition? A cue-utilization approach to judgments of learning (JOLs) is outlined, distinguishing 3 types of cues for JOLs: intrinsic, extrinsic, and mnemonic. In 4 experiments using paired-associates learning, item difficulty (intrinsic) exerted similar effects of JOLs and recall. In contrast, the extrinsic factors of list repetition, item repetition within a list, and stimulus duration affected JOLs less strongly than recall, supporting the proposition that extrinsic factors are discounted in making JOLs. Although practice impaired calibration, increasing underconfidence, it did improve resolution (i.e., the recall-JOL correlation). This improvement was seen to reflect a shift in the basis of JOLs with practice, from reliance on intrinsic factors, towards greater reliance on mnemonic-based heuristics.