Columbus, Ohio is 5.7 times larger than San Francisco.
Area: 694 km2 calculated
Columbus is the capital of and the largest city in the U.S. state of Ohio. It is the 15th largest city in the United States with a population of 822,553. It is the core city of the Columbus, OH Metropolitan Statistical Area, which encompasses a ten county area. Wikipedia
Area: 122 km2 calculated
San Francisco, officially the City and County of San Francisco, is the cultural center and a leading financial hub of the San Francisco Bay Area and Northern California. Wikipedia