Two small tools that do the arithmetic this site runs on. Use them on your own recipes: if a dish cannot state its cost per serving, it cannot claim to be a budget dish.
Add up a recipe's ingredient costs and divide by real servings. The simplest honest number in budget cooking, calculated for you.
Turn package prices into ingredient costs: enter a package price, its size, and how much the recipe uses, line by line, and get the batch total.