How to Read Nutrition Facts: per 100 g, per Serving and % Daily Value

What the numbers on a nutrition table mean, why FoodFactly shows values per 100 g, and how to convert them to the amount you actually eat.

This guide is awaiting editorial review.

Every food page on FoodFactly starts from the same reference amount: 100 grams of the food (100 ml for some drinks). Using one fixed amount makes foods directly comparable. A serving size, by contrast, differs from product to product and from one country's labeling rules to another.

Per 100 g versus per serving

To get the value for the amount you eat, multiply the per-100 g value by your weight in grams and divide by 100. For example, a food with 12 g of protein per 100 g provides 12 × 150 / 100 = 18 g of protein in a 150 g portion. The serving calculator on each food page does this for you, using the household measures (cups, pieces, slices) that the data source has weighed.

Household measures are specific to a food: one cup of chopped broccoli and one cup of cooked rice weigh very different amounts. FoodFactly only offers a measure such as "1 cup" when the source reports its weight for that particular food.

% Daily Value

The percent Daily Value (%DV) compares an amount with a reference intake. FoodFactly uses the Daily Values the U.S. Food and Drug Administration set for food labels for adults and children aged 4 and over. A value of 20% means that 100 g of the food provides one fifth of that reference amount. Daily Values are general label references, not personal recommendations; individual needs vary.

Missing values

When a source has not measured or reported a nutrient, FoodFactly shows it as not reported. A missing value is not the same as zero, and we never fill gaps with estimates.

Updated November 6, 2026. General information, not medical advice. See the editorial policy.