Ankeny is a municipality situated in Polk County, Iowa, United States, serving as a suburban extension of the state capital, Des Moines, within the Des Moines-West Des Moines, IA metropolitan statistical area.According to the 2020 census, Ankeny boasts a population of 67,887, ranking as the seventh most populous city in the state. Recognized for its rapid growth, it stands among the swiftest-developing cities in Iowa. The city's incorporated area currently spans 29.14 square miles.