To be able to monitor caffeine intake, you first have to get a general idea of much caffeine is in a cup of coffee. According to the USDA, regular, brewed coffee contains about 95 milligrams of caffeine per 8-ounce cup. “This is based on average values of home-brewed and fast-food coffee,” Beth Witherspoon, M.P.H., R.D.N., registered dietitian consultant for Community Coffee Company, tells SELF.