A cup of plain black coffee only has two calories and contains no fat. Adding 1 tablespoon of table sugar adds 49 calories, and 1 tablespoon of half-and-half adds 20 calories. A 12-ounce cup of plain black coffee normally contains over 100 milligrams of caffeine, depending on the type.
Calories quickly add up for coffee drinkers who purchase coffee at specialty coffee shops. Generally, coffee shops serve larger sizes than a standard 6- or 8-ounce cup. Many are as large as 20 ounces, or roughly three times the regular serving size. These types of coffee also have extra ingredients, such as chocolate or caramel, which add calories.