New York City is 4.4 times larger than Brooklyn (NYC borough).
Area: 180 km2 calculated
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
Area: 784 km2 calculated
New York is the most populous city in the United States and the center of the New York metropolitan area, the premier gateway for legal immigration to the United States and one of the most populous urban agglomerations in the world. Wikipedia