A cup of brewed coffee generally contains more caffeine than a cup of tea. Coffee typically has between 95 to 200 milligrams of caffeine per cup, while black tea ranges from about 14 to 70 milligrams, green tea from 20 to 45 milligrams, and white tea from 6 to 60 milligrams. Despite tea leaves containing more caffeine than coffee beans by weight, the brewing process extracts more caffeine from coffee, resulting in a stronger caffeine concentration per cup in coffee than in tea.