Oklahoma City (/ˌoʊkləˈhoʊmə -/ OH-klə-HOH-mə -), often shortened to OKC, is the capital and most populous city of the U.S. state of Oklahoma. It is the 20th-most populous U.S. city and 8th largest in the Southern United States, with a population of 681,054 at the 2020 census. The Oklahoma City metropolitan area, with an estimated 1.49 million residents, is the largest metropolitan area in the state and 42nd-most populous in the country. It is the county seat of Oklahoma County, with the city limits extending into Canadian, Cleveland, and Pottawatomie counties; however, areas beyond Oklahoma County primarily consist of suburban developments or areas designated rural and watershed zones. Oklahoma City ranks as the tenth-largest city by area in the United States when including consolidated city-counties, and second-largest when such consolidations are excluded. It is also the second-largest state capital by area, after Juneau, Alaska.
Oklahoma City has one of the world's largest livestock markets. Oil, natural gas, petroleum products, and related industries are its economy's largest sector. The city is in the middle of an active oil field, and oil derricks dot the capitol grounds. The federal government employs a large number of workers at Tinker Air Force Base and the United States Department of Transportation's Mike Monroney Aeronautical Center (which house offices of the Federal Aviation Administration and the Transportation Department's Enterprise Service Center, respectively).