Oklahoma City, often shortened to OKC, is the capital and largest city of the U.S. state of Oklahoma. The county seat of Oklahoma County, the city ranks 27th among United States cities in population. The population grew following the 2010 Census, with the population estimated to have increased to 631,346 as of July 2015. As of 2015, the Oklahoma City metropolitan area had a population of 1,358,452, and the Oklahoma City-Shawnee Combined Statistical Area had a population of 1,459,758 residents, making it Oklahoma's largest metropolitan area.Oklahoma City's city limits extend into Canadian, Cleveland, and Pottawatomie counties, though much of those areas outside the core Oklahoma County area are suburban or rural. The city ranks as the eighth-largest city in the United States by land area.Oklahoma City has the largest municipal population of any city in the Great Plains region of the central United States, as well as all neighboring states to Oklahoma, excluding Texas and Colorado.