The average cup of American-style coffee contains about 100 to 150 milligrams of caffeine; a properly prepared demitasse or single serving of espresso 80 to 120 milligrams. The average cup of tea delivers about 40 milligrams; the average chocolate bar about 20 to 60. A 12-ounce bottle of cola drink contains 40 to 60 milligrams, about as half as much as a cup of coffee.
