Calories. The calorie content of a McDonald's iced vanilla coffee varies depending on the size of the beverage and any additional ingredients, such as creamer or extra sugar. A small iced vanilla coffee with regular syrup contains 130 calories, at 8 fluid ounces.A medium iced vanilla coffee with regular syrup is 11.5 fl oz and contains 190 calories, while a large iced vanilla coffee has 270 calories.f cream or sugar are added, though, the calories can start to add up fast. McDonald's offers iced coffee drinks with a flavor sweetener choice for the same price as a regular iced coffee.