Milwaukee is 2.1 times larger than Grand Rapids, Michigan.
Area: 117 km2 calculated
Grand Rapids is a city in the U.S. state of Michigan. It is located on the Grand River about 25 miles east of Lake Michigan. As of the 2010 census, the city population was 188,040. Wikipedia
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