How to Count Carbs

1). Eat foods using the predetermined carbohydrate count. Most food comes with a carbohydrate count per serving already mapped out. By eating food in its allotted serving, you will take most of the headache out of counting the carbs yourself. Remember, however, that food is usually measured by weight or volume, and while most containers list both of these, some only use one.
2). Measure the food you eat. If you plan on eating a different serving size than the one that is recommended, it will become necessary to measure the food. Make sure you are using the same type of measuring system with which the serving size has been determined. If you are using weight, you will need a scale to measure the amount of food you are eating. If the measurement is in volume (such as a cup), use the appropriate measuring medium.
3

Calculate the carbs in your food. There is a simple way to do this. First of all, you will need either a book or index that tells you the average amount of carbohydrates in the type of food you will be eating. (Follow the links in Resources.) After you have weighed or measured the portion, look up the carbohydrate content in your book or index. Multiply your portion measurement by the carb content that is indicated. The result will be the carbohydrate content of the food you have measured.
4). After you have started counting carbs, begin keeping a diary of the food you eat regularly. This will save time when you want to look up foods you have previously calculated, so you won't have to do it over again. You will also receive a good indication of your eating habits and areas in which you may need to improve.
5). Keep tabs on "lost" carbs. Remember that, if you intend to cook your food after you have measured it, any ingredient you add after you have measured it (no matter how small) may need to be counted as well. For example, if you counted the carbs in a potato before fully preparing it, and you intend to boil or bake it and add butter, the butter will subsequently have to be counted as well to obtain an accurate calculation.