In 100 grams of cornstarch, there are 91 gms of carbohydrates. It is a thickening agent which uses in stews, soups, and other food.  This is basically a smooth and white powder uses in a variety of things like cooking, baking to reduce friction and chaffing. It is made from the starchy part of a corn kernel. Most of the cornstarch calories contain carbohydrates. If we talk about macronutrients, a one-ounce serving size of cornstarch is about 106 calories and includes 25.6 grams of carbohydrates.