The hamlet is also called "Clarence Hollow", or just "The Hollow", due its location centered at the base of an indentation in the Onondaga Escarpment formed by Ransom Creek. The Clarence Historical Society is located on Main Street. During the time of its founding, Clarence village was called "Pine Grove" and later "Ransomville".
According to the United States Census Bureau, the CDP has a total area of 2.91 square miles (7.54 km2), of which 2.85 square miles (7.37 km2) is land and 0.066 square miles (0.17 km2), or 2.23%, is water.