Collins Cooling & Heating Co
Free Online Estimater
Keep in mind that this method has a variance of +/- 10% in most cases and in rare cases +/- 20% but, it's a quick way to get a projected idea of capacity of furnace and or a/c for the size of your house.
Due to your home efficiency, some houses will require more and some need less but, for most houses this method works well.
