Sonic Drive-In, more commonly known as Sonic, is an American drive-in fast-food restaurant chain based in Oklahoma City, Oklahoma. As of August 31, 2015, 3,526 restaurants were in 43 U.S. states. In 2011, it was ranked 10th in QSR Magazine's rankings of the top 50 quick-service and fast-casual restaurant brands in the nation. Known for its use of carhops on roller skates, the company annually hosts a competition to determine the top skating carhop in its system. It also hosts, with Dr Pepper, an internal competition between drive-in employees.