Cow milk that has been skimmed of fat contains 83 calories per cup, according to the USDA. This milk is normally labeled fat free or non-fat and contains 0.5 percent or less butterfat.
The caloric value of commercial milk is determined by the amount of fat that is skimmed from whole, raw milk. Milk that has been skimmed to 1 percent butterfat has 104 calories per cup. One cup of milk containing 2 percent butterfat has 122 calories. The calorie count in one cup of whole, or full-fat milk is 149. Milk that is considered whole contains 3.5 to 4 percent butterfat.