FDA rounding rules decide what number goes on a Nutrition Facts label. A lab report might say a serving has 143 mg of sodium and 0.44 g of saturated fat. The label must say 140 mg and 0 g. Every nutrient has its own increments and cut-offs, set out in 21 CFR 101.9(c). This page explains them and includes a checker. Enter your lab values and the values on your label, and it tells you, line by line, whether each one follows the rules and why.
FDA Rounding Rules Checker
For each nutrient, enter the unrounded value from your lab report and the value declared on the label (a number, or “<1” / “less than 1”). Leave rows blank to skip them. Each row is checked against 21 CFR 101.9(c).
Educational aid, not a compliance certification. This checks rounding only, for the standard label for adults and children 4+. It does not check analytical accuracy (FDA’s Class I/II compliance limits in 101.9(g)), claims, or whether a nutrient may be omitted in your case. Vitamin and mineral increments come from FDA’s nonbinding 2019 guidance, so a mismatch there shows as “Check”, not “Fail”.
The checker needs JavaScript. The full rounding table is in the article below.
This table covers every nutrient on the standard label. “Nearest 5 mg” means 7 mg becomes 5 mg and 8 mg becomes 10 mg. The checker rounds exact halves up (2.25 g becomes 2.5 g), which is ordinary arithmetic rounding. The regulation itself doesn’t spell out tie-breaking.
Nutrient
Amount per serving
Declare as
21 CFR
Calories
Less than 5
0 (optional)
101.9(c)(1)
5 up to and including 50
Nearest 5
Above 50
Nearest 10
Total fat, saturated fat, trans fat, polyunsaturated and monounsaturated fat
Less than 0.5 g
0 g
101.9(c)(2)
0.5 g to under 5 g
Nearest 0.5 g
5 g and above
Nearest 1 g
Cholesterol
Less than 2 mg
0 mg (or omit, see below)
101.9(c)(3)
2 to 5 mg
“Less than 5 mg”
Above 5 mg
Nearest 5 mg
Sodium
Less than 5 mg
0 mg
101.9(c)(4)
5 to 140 mg
Nearest 5 mg
Above 140 mg
Nearest 10 mg
Total carbohydrate, dietary fiber, soluble and insoluble fiber, total sugars, added sugars, sugar alcohol, protein
Less than 0.5 g
0 g (optional) or “less than 1 g”
101.9(c)(6), (c)(7)
0.5 g to under 1 g
“Less than 1 g”, or 1 g
1 g and above
Nearest 1 g
Fluoride (voluntary)
Less than 0.1 mg
0 mg
101.9(c)(5)
0.1 to 0.8 mg
Nearest 0.1 mg
Above 0.8 mg
Nearest 0.2 mg
“Less than” can be written with the symbol: “<1g” and “<5mg” are allowed by 101.9(d)(7)(i).
Calories
Calories are declared to the nearest 5 up to and including 50, and to the nearest 10 above 50. So 47 calories is 45, 48 is 50, 54 is 50 and 55 is 60. Below 5 calories, the amount “may be expressed as zero”. It’s an option, so a label showing 5 for a 3-calorie serving also follows the rule.
Fats
Total fat and each fatty acid line use the same steps. Below 0.5 g the regulation says the content “shall be expressed as zero”. That’s not optional, so 0.44 g of saturated fat declared as 0.5 g is wrong. If total fat is under 0.5 g and you make no fat, fatty acid or cholesterol claims, you can drop the saturated and trans fat lines. You then add “Not a significant source of saturated fat” (or trans fat) at the bottom.
Cholesterol
Under 2 mg can be shown as 0 mg. With no fat or cholesterol claims, you can leave cholesterol off and state “Not a significant source of cholesterol”. From 2 to 5 mg, you may say “less than 5 mg”. Above 5 mg, round to the nearest 5 mg.
Sodium
Sodium has a change of step at 140 mg. From 5 to 140 mg it’s rounded to the nearest 5 mg, and above 140 mg to the nearest 10 mg. So 143 mg is declared as 140 mg, not 145. That’s the mistake in the checker’s example. Potassium used to follow the same rule, but since the 2016 final rule it is treated like the other minerals (see below).
Carbohydrates and protein
These are all declared to the nearest gram, with two options for small amounts. Under 1 g, you can say “less than 1 gram”. Under 0.5 g, you can say zero. That means 0.7 g of fiber can be declared as “<1g” or as “1g”, and both pass. Fiber, total sugars and added sugars under 1 g can also be left off entirely when no related claim is made, with a “Not a significant source of …” statement instead.
Vitamins and Minerals
Vitamins and minerals have two numbers on the label, an amount and a %DV, and they round differently.
The %DV is rounded to the nearest 2% up to and including 10%, the nearest 5% above 10% up to and including 50%, and the nearest 10% above 50% (101.9(c)(8)(iii)). Below 2%, it may be shown as zero or with an asterisk and “Contains less than 2 percent of the Daily Value of this nutrient”. For vitamin D, calcium, iron and potassium, the nutrient may instead be left off with “Not a significant source of …”.
The amount must use “the units of measurement and the levels of significance” of the Daily Value table. Extra decimal places are allowed when needed to show small amounts (101.9(c)(8)(iii)). In guidance revised in December 2019, FDA translated this into increments based on the size of each Daily Value:
Daily Value
Recommended increment
Nutrients
500 mg or mcg and above
Nearest 10
Calcium, potassium, phosphorus, chloride, choline, vitamin A
Because the guidance is nonbinding, the checker marks a vitamin or mineral that doesn’t match it as “Check” rather than “Fail”. One example is potassium declared as 235 mg (as on FDA’s 2016 sample label) instead of 240 mg.
Common Rounding Mistakes
Rounding twice. Rounding a recipe’s ingredients and then rounding the total produces errors. Round once, at the end, from the unrounded total per serving.
Using the sodium step for everything. Sodium switches from 5 mg to 10 mg steps at 140 mg; cholesterol always uses 5 mg steps. Fat switches from 0.5 g to 1 g steps at 5 g.
Declaring 0.5 g of fat for 0.4 g. Below 0.5 g, fat must be zero.
Computing %DV from inconsistent numbers. You may base %DV on the declared amount or on the unrounded amount (101.9(d)(7)(ii)), but use one method for the whole label.
Using the old potassium rule. Since the 2016 rule, potassium is a mineral with a Daily Value of 4,700 mg, not a sodium-style 5/10 mg nutrient.
Rounding is separate from accuracy. FDA checks the declared values against laboratory analysis using the compliance criteria in 101.9(g). For example, “Class I” added nutrients must be at least 100% of the declared value, and sodium, sugars and saturated fat can’t exceed 120% of it. Our article on how Nutrition Facts are verified on food labels covers that side.
Frequently Asked Questions
Where are the FDA rounding rules written?
In 21 CFR 101.9(c), in the paragraph for each nutrient. FDA’s Food Labeling Guide also has a summary table (Appendix H). Where the two differ, the regulation as amended by the 2016 final rule controls.
Does the checker handle “less than 1 g”?
Yes. Type “<1”, “less than 1” or “contains less than 1 gram” in the Declared box. The checker accepts it wherever the regulation allows it and tells you when it doesn’t. For example, “less than 1 g” isn’t a permitted way to declare fat.
Do the same rules apply to Supplement Facts?
Supplement Facts panels (21 CFR 101.36) refer to many of the same rounding rules, but they have their own format and some different provisions. This checker is for Nutrition Facts labels.
Link to This Tool
Food science instructors, extension agents and health departments are welcome to link to this page. A plain-text citation:
Compliance Naturally. FDA Rounding Rules Checker for Nutrition Facts Labels (21 CFR 101.9(c)). https://compliancenaturally.com/fda-rounding-rules/
No embed code is needed. The page is updated if FDA changes the rules.
This checker is an educational aid, not a compliance certification. Check final labels against the current regulation.
