Solo masturbation is common across adulthood, with 12-52% of women and 28-69% of men having masturbated alone in the past month. For some, masturbation is a source of pleasure, joy, relaxation, and fulfillment. For others, masturbation is seen as wrong and immoral, which can lead to feelings of shame and spiritual turmoil. Past research on whether solo masturbation is associated with health and well-being vs harm and poor health has yielded mixed results. Years of social psychological research has shown that attitudes towards a behavior can predict the experience of that behavior. Thus, understanding individuals’ attitudes towards solo masturbation could disentangle mixed findings on the association between solo masturbation and well-being. The most widely used measure of masturbation attitudes, created in 1975, has limitations from current standards of scale development: the 1975 measure is too long, uses dated language, and does not distinguish between positive and negative attitudes. Therefore, the goal of this study is to develop a psychometrically sound and brief scale of attitudes toward solo masturbation. Data will be collected via a 10-minute online survey of 1500 adults. Participants will respond to a pool of 24 newly written items assessing positive and negative attitudes towards solo masturbation and report on related constructs. These 24 attitude items will be reduced to a 10-item scale of positive and negative attitudes using exploratory factor analysis. Convergent and divergent validity will be assessed with Pearson’s correlations between the new attitude scale and related constructs to be presented by a colleague, Gabriella Loredo Marquez. We expect these positive and negative subscales to be correlated with the old attitude measure, religiosity, attitudes towards sex, masturbation frequency, and masturbation pleasure. Thus, this new measure will shed light on why solo masturbation is associated with positive well-being for some, and negative well-being for others.