Fremont, California is 3.5 times larger than Sunnyvale, California.
Area: 200 km2 calculated
Fremont is a city in Alameda County, California. It was incorporated on January 23, 1956, from the merger of five smaller communities: Centerville, Niles, Irvington, Mission San Jose, and Warm Springs. Wikipedia
Area: 57 km2 calculated
Sunnyvale, officially the City of Sunnyvale, is a city located in Santa Clara County, California. As of the 2010 United States Census, the population was 140,095. The city is one of the major cities that make up the Silicon Valley located in the San Francisco Bay Area. Wikipedia