Abstract
The Seity Check-In (SCI) is a new, multidimensional measure of momentary well-being that features both hedonic and eudaimonic elements. It imposes minimal cognitive demands on respondents, asking them to report their current levels of energy, direction, belonging, and joy by selecting one of five "happy face" emojis for each dimension. This task can be completed in just a few seconds. The psychometric model underlying the SCI is formative, with each of the four dimensions contributing directly to well-being. A preregistered data analysis of 564 individuals who were living in the United States and completed the SCI and other instruments found high correlations (r = .84 to.86) with two established measures of well-being, providing strong evidence for criterion validity. Furthermore, responses for each SCI dimension were highly correlated (r = .80 to.85) with items adapted from other scales designed to assess the same dimension, providing strong evidence for construct validity. Analyses of open-ended mood descriptions corroborated the psychometric findings. We conclude that the SCI offers considerable utility for assessing well-being, especially in applied situations.