Orange County, California is 2.8 times larger than Charlotte, North Carolina.
Area: 733 km2 calculated
Charlotte is the largest city in the U.S. state of North Carolina and the seat of Mecklenburg County. In 2013, the estimated population of Charlotte according to the U.S. Census Bureau was 792,862, making it the 16th largest city in the United States based on population. 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