What does a good life look like? The present research investigated individual differences in people's perceptions of the factors that are most important for living a good life using two waves of data in probability samples from the U.S. (MIDUS; N = 4,041) and Japan (MIDJA; N = 381). We examined country- and age-related similarities and differences in perceptions of a good life and associations of perceptions of a good life with experiences of wellbeing and physical health. Some factors were considered important for living a good life in both countries and across age (e.g., positive relationships with family), whereas other factors varied between countries (e.g., U.S. participants were more likely to perceive faith as important) and by age (e.g., younger adults were more likely to perceive having a good job as important). Further, perceptions of a good life were related to experiences of wellbeing and physical health concurrently and prospectively. This research informs our understanding of how people differ from one another in their perceptions of a good life, and how these differences may matter for individuals' experiences of a good life.