How We Calculate % Daily Value
USDA FoodData Central gives the nutrient content of a food. The % Daily Value (%DV) puts one of those numbers in context: it is the share of a reference daily amount that a serving provides. The reference amounts are set by the U.S. Food and Drug Administration for the Nutrition Facts label (21 CFR 101.9), based on a 2,000-calorie diet.
The formula
%DV = amount in the serving ÷ FDA Daily Value × 100
FoodData Central stores nutrients per 100 grams. When a product declares a serving size in grams we scale to that serving first; otherwise the %DV is shown per 100 g and labelled as such on the page.
Daily Values we use
| Nutrient | Daily Value |
|---|---|
| Total fat | 78 g |
| Saturated fat | 20 g |
| Cholesterol | 300 mg |
| Sodium | 2,300 mg |
| Total carbohydrate | 275 g |
| Dietary fiber | 28 g |
| Potassium | 4,700 mg |
| Calcium | 1,300 mg |
| Iron | 18 mg |
| Magnesium | 420 mg |
| Zinc | 11 mg |
| Vitamin C | 90 mg |
| Vitamin A | 900 µg RAE |
| Vitamin D | 20 µg |
What we deliberately leave out
- Total sugars. The FDA %DV is defined for added sugars (Daily Value 50 g). FoodData Central does not separate added from naturally occurring sugars, so a %DV for total sugars would overstate the figure for fruit, milk and similar foods. We show grams of total sugar without a %DV.
- Protein. A %DV for protein is optional on the U.S. label and only required when a claim is made or the food is for infants and children under 4. We show grams only.
- Trans fat. The FDA sets no Daily Value for it.
Limitations
- The Daily Values are a single national reference for adults and children 4+. They are not a personal target — needs vary with age, sex, activity and health.
- For branded foods the underlying nutrient numbers are manufacturer-declared and not independently verified by USDA; any error there flows into the %DV.
- Where a serving size is missing or not in grams, the %DV is per 100 g, which is larger than a typical serving for calorie-dense foods.
Sources: U.S. Food and Drug Administration, 21 CFR 101.9 (Nutrition labeling of food); U.S. Department of Agriculture, FoodData Central. Back to About the Data.