Perceptions of personal risk (i.e. risk likelihood) occupy a central role in theories of individual health behavior. There is no agreement, however, concerning the best approach for measuring these perceptions. We compared a percentage scale with a seven-point, verbally labeled scale. Data from college student subjects (N = 215) showed that the correlations between risk factors and risk likelihood judgments for seven health problems were no stronger with one scale than the other. Suggestions for when to use each scale are given.