The Bronx (NYC borough) is 16% larger than Rochester, New York.
Area: 96 km2 calculated
Rochester is a city in Monroe County, New York, south of Lake Ontario in the United States. Known as the World's Image Center, it was also once known as the Flour City, and more recently as The Flower City, annually hosting the Lilac Festival. It is the county seat for Monroe County. Wikipedia
Area: 112 km2 calculated
The Bronx is the northernmost of the five boroughs of New York City, in the U.S. state of New York. Coextensive with Bronx County, it was the last of the 62 counties of New York State to be incorporated. Wikipedia