Nutrition method

Nutrition on green.recipes is calculated by code from USDA FoodData Central, the public food composition database of the United States Department of Agriculture. We use two of its data sets: SR Legacy (April 2018) and Foundation Foods (April 2025).

How the numbers are made

1. Each ingredient is matched to the USDA record that fits the state in which the recipe weighs it, for example dried or cooked, canned and drained, raw or roasted.
2. The gram weight in the recipe is multiplied by the record's values per 100 grams.
3. The totals are divided by the number of servings and rounded: calories and sodium to whole numbers, other values to one decimal place.
4. When a USDA record has no energy value, energy is calculated from protein, carbohydrate and fat with the general factors of 4, 4 and 9 kilocalories per gram.

What the numbers do not capture

• Brands and varieties differ, especially for tahini, bread, stock and cheese.
• All oil in the ingredient list is counted, including oil that stays in the pan.
• Salt added to taste beyond the stated amount is not counted.
• An ingredient without a matching USDA record is left out, and the recipe lists it under references.

The values are estimates for general information, not medical or dietary advice.

Cups and spoons

US cup weights come from the household measures in the same USDA records where available (1 US cup is 236.6 ml). When an ingredient has no cup measure, it is shown in grams. Items you count, such as garlic cloves, keep their count and show the typical weight.

Diet labels and allergens

Vegan, vegetarian, gluten-free, dairy-free and nut-free labels, and the allergen list (sesame, tree nuts, peanuts, milk, egg, gluten, soy, celery, mustard, fish, crustaceans, molluscs and lupin), are assigned by fixed rules from ingredient names and notes. Packaged ingredients can contain allergens that are not in their name, so check product labels if you cook for someone with an allergy.

Source: U.S. Department of Agriculture, Agricultural Research Service. FoodData Central. fdc.nal.usda.gov.