This is how we calculate nutrition for RecipeFab recipes. Most recipes include an estimated Nutrition Facts box, and this page explains exactly how those numbers are calculated, what they include, and what they leave out.
Where the data comes from
We use ingredient data from USDA FoodData Central, the U.S. Department of Agriculture’s public food composition database. For each ingredient we use the closest plain, standard entry (for example, all-purpose white flour or unsalted butter). Most values come from the SR Legacy dataset. For a branded product that has no general USDA entry, such as panko or a specific cookie, we use the label values in FoodData Central’s Branded Foods data. Each recipe’s nutrition note lists the FoodData Central ID numbers we used, so you can check them.
How We Calculate Nutrition, Step by Step
- Every ingredient amount in the recipe is converted to grams, using USDA portion weights for cups, tablespoons and individual items.
- The nutrient values for each ingredient are added up for the whole recipe.
- The total is divided by the number of servings stated in the recipe. For things like cakes, ice cream or syrups, the serving is labelled clearly, such as one slice or one tablespoon.
- Numbers are rounded the same way U.S. food labels are rounded.
What is included and what is not
Everything listed with an amount is included, as well as toppings or sauces that are part of the dish as served. Ingredients listed as optional or “to taste”, garnishes, water and salt used only for boiling, and oil used for deep-frying are not included, because the amount actually eaten varies too much to estimate honestly. When a recipe is deep-fried, the Nutrition Facts box says so.
How to use these numbers
The values are estimates. Brands, the exact size of your ingredients and how you portion the dish will all change the real numbers. They are meant as general information, not medical or dietary advice. If you need precise figures for a health condition, please talk to a doctor or registered dietitian.
Questions
If a number looks wrong, let us know through the Contact page and we will recheck the calculation. You can also read our editorial policy for how recipes are written and updated.