Orange County, California is 3.8 times larger than Guam.
Area: 544 km2 World Factbook
Population: 161,001 (July 2014) World Factbook
Guam is an organized, unincorporated territory of the United States in the western Pacific Ocean. It is one of five U.S. territories with an established civilian government. Wikipedia
Area: 2,064 km2 calculated
Orange County is a county in the U.S. state of California. As of the 2010 census, the population was 3,010,232 making it the third-most populous county in California, the sixth-most populous in the United States, and it more populous than twenty-one U.S. states. Its county seat is Santa Ana. Wikipedia