Enter in the info from the package in grams or ounces, whichever you prefer to measure in. So if a serving is 28 g for 100 calories, enter the food in with that info. Then, when you pick that entry on the day you eat it you will just enter in the amount of grams you did eat, say 14, and the tracker will add the 50 calories of food that you ate.
-google first. ask questions later.