Milwaukee is the most populous city in the U.S. state of Wisconsin and the county seat of Milwaukee County. With a population of 577,222 at the 2020 census, Milwaukee also is the 31st-most populous city in the United States, and the fifth-most populous city in the Midwest. It is the central city of the Milwaukee metropolitan area, the 40th-most populous metro area in the U.S.. Milwaukee is categorized as a "Gamma minus" city by the Globalization and World Cities Research Network, with a regional GDP of over $102 billion in 2020.