How many calories does coffee have?

There is considerable confusion over the caloric content of coffee. Not all coffee drinks are high in calories. Coffee - without additives - is almost a zero-calorie drink.

Here is a complete guide to understanding coffee calories.

Coffee is almost Zero Calorie
According to the USDA nutrient database - an 8 ounce cup of coffee (brewed from grounds) has just 2 (yes two) Calories. The calories come from a tiny amount of protein and some mono-unsaturated oils.
The coffee bean has oils in it (which is why a barista often needs to clean their espresso machine to prevent an oily build up). Sometimes a really bad coffee can be due to the oils in it becoming rancid (this often occurs from dark roasts, which cause a subsequent release of oils - if the beans are stored for a long time the oils may go slightly rancid).

So: coffee beans + water = virtually calorie-free.

It's about Milk and Sugar
About a coffee high in calories and about the additives put in it. Caffeine is a bitter chemical and products containing caffeine are bitter - so to sweeten them up - with milk, sugar, or syrups.
The larger the drink volume - the more milk will be getting. With espresso-based drinks (latte, cappuccino) - the amount of water in the drink is minimal (typically 45mls / 1.5 fl. ounces per espresso shot). The math: a 16 ounces Grande Latte from Starbucks will have two espresso shots (~ 3 oz) -- that leaves around 13 ounces of milk (depending on how much foam tops the drink) - so there's 198 Calories already (if the milk is 2% reduced fat).

Add in cream, a pump of flavored syrup, and some sugar - and it's a very calorie-dense drink - more like sweetened milk than coffee.

Calories in Common Coffee Drinks - Beverage Volume (oz) Calories

Instant coffee 1 rounded tsp dry powder 4
Instant coffee 4
Espresso Coffee 1
Brewed Coffee 2
McDonald's Cappuccino 130
McDonald's Latte 180
McDonald's Mocha 330
McDonald's Brewed Coffee (Large) 0
Dunkin Donuts Latte 120
Dunkin Donuts Cappuccino 80
Dunkin Donuts Mocha Swirl Latte 230
Dunkin Donuts Brewed Coffee 15
Starbucks Brewed Coffee 5
Starbucks Caffè Americano 15
Starbucks Caffè Latte 220
Starbucks Caffè Mocha (no whip) 290
Starbucks Caffè Mocha (whip) 360
Starbucks Cappucino 140
Starbucks Peppermint White Chocolate Mocha (whip) 560
Starbucks Caffe Vanilla Frappucino Blended Coffee (whip) 430
Starbucks Hot Chocolate (no whip) 330

Coffee Extras

Many people use non-dairy creamers in their coffee. However, as the chart below shows - these still contain Calories. Extras Calories (per Tablespoon)
Cream 52
Half-and-half 20
Whole milk 9
Fat-free milk 5
Sugar 48
McDonald's Coffee Cream (liquid) 20
Plain nondairy creamer (powder) 33
Plain, light nondairy creamer (powder) 25
Flavored nondairy creamer (powder) 45
Flavored, reduced-fat nondairy creamer (powder) 40
Plain nondairy creamer (liquid) 20
Plain, light nondairy creamer (liquid) 10
Flavored nondairy creamer (liquid) 35
Flavored, reduced-fat nondairy creamer (liquid) 20