Austin, Texas is 7.2 times larger than Boston.
Area: 933 km2 calculated
Austin is the capital of Texas and the seat of Travis County. Located in Central Texas and the American Southwest, it is the 11th-most populous city in the United States of America and the fourth-most populous city in the state of Texas. Wikipedia
Area: 129 km2 calculated
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