As part of quick-service restaurant magazine QSR's feature on the top 50 quick service/fast casual brands in the country in 2010, you can view their burger chain rankings with info on total sales and units. According to the chart, the top five burger chains are McDonald's, Burger King, Wendy's, Sonic, and Jack in the Box. Five Guys had the most growth, while Hardee's had the highest decrease in units.