Detroit is 53% larger than Milwaukee.
Area: 251 km2 calculated
Milwaukee is the largest city in the U.S. state of Wisconsin, the 30th most populous city in the United States, and 39th most populous region in the United States. It is the county seat of Milwaukee County and is located on the southwestern shore of Lake Michigan. Wikipedia
Area: 383 km2 calculated
Detroit is the most populous city in the U.S. state of Michigan and the largest city on the United States-Canada border. It is the seat of Wayne County, the most populous county in the state. Wikipedia