Personal identity formation constitutes a crucial developmental task during the teens and 20s. Using a recently developed five-dimensional identity model, this cross-sectional study (N = 5834) investigated age trends from ages 14 to 30 for different commitment and exploration processes. As expected, results indicated that, despite some fluctuations over time, commitment processes tended to increase in a linear fashion. Exploration in breadth and exploration in depth were characterized by quadratic trends, with the highest levels occurring in emerging adulthood. Further, the functionality of these identity processes, and especially of exploration, changed over time. Exploration in breadth and exploration in depth were strongly related to commitment processes especially in adolescence and emerging adulthood, but these exploration processes became increasingly associated with ruminative exploration and depressive symptoms in the late 20s. Theoretical implications and suggestions for future research are outlined.