What “serving size” means on a food label
The words below are the regulation's own. They are quoted exactly from the United States Code of Federal Regulations.
The definition
The term serving or serving size means an amount of food customarily consumed per eating occasion by persons 4 years of age or older which is expressed in a common household measure that is appropriate to the food.
Except as provided in § 101.9(h)(3), all nutrient and food component quantities shall be declared in relation to a serving as defined in this section.
Plain facts about this rule
Every figure on a Nutrition Facts label is for the serving size printed at the top of that label. The amount a person eats may be more or less than that.
To see the figures for the amount you will eat, use Check a label.
Source
- Text used:
- Electronic Code of Federal Regulations (eCFR), Title 21, Part 101, as in force on 6 October 2026
- Checked on:
- 11 October 2026