Body functionality has been identified as an important dimension of body image that has the potential to be useful in the prevention and treatment of negative body image and in the enhancement of positive body image. Specifically, cultivating appreciation of body functionality may offset appearance concerns. However, a scale assessing this construct has yet to be developed. Therefore, we developed the Functionality Appreciation Scale (FAS) and examined its psychometric properties among three online community samples totaling 1042 women and men (ns = 490 and 552, respectively). Exploratory factor analyses revealed a unidimensional structure with seven items. Confirmatory factor analysis upheld its unidimensionality and invariance across gender. The internal consistency, test-retest reliability, criterion-related, and construct (convergent, discriminant, incremental) validity of its scores were upheld. The FAS is a psychometrically sound measure that is unique from existing positive body image measures. Scholars will find the FAS applicable within research and clinical settings.