Brooklyn (NYC borough) is 39% larger than Boston.
Area: 129 km2 calculated
Population: 636,479 (2012)
Boston is the capital and largest city of the Commonwealth of Massachusetts in the United States. Boston also serves as county seat of Suffolk County. Wikipedia
Area: 180 km2 calculated
Population: 2,565,635 (2012)
Brooklyn is the most populous of New York City's five boroughs, with about 2.6 million people, as well as the second-largest in area. Wikipedia