Cary is a village located in Algonquin Township, McHenry County, Illinois, United States. The population was 15,531 at the 2000 census. A 2003 special census put the village's population at 17,827.
Cary is located at 42°12′47″N 88°14′54″W / 42.21306°N 88.24833°W / 42.21306; -88.24833 (42.2129566, -88.2483260).
According to the United States Census Bureau, the village has a total area of 5.3 square miles (13.8 km²), of which, 5.2 square miles (13.6 km²) are land and 0.1 square mile (0.2 km²) of it (1.13%) is water. It is located on the Fox River.