Magnesium — FDA Daily Value
The FDA Daily Value for Magnesium is 420 mg for adults and children 4 or more years of age — a Reference Daily Intake (RDI), a fixed target not tied to calories. It changes by population group; see the exact numbers below.
Population group
Daily Value
5% DV
20% DV
Adults & children 4+
420 mg
21 mg
84 mg
Children 1–3 years
80 mg
4 mg
16 mg
Pregnant & lactating
400 mg
20 mg
80 mg
Infants 0–12 months
75 mg
3.75 mg
15 mg
Source: the FDA Daily Values in 21 CFR 101.9 and the FDA's Nutrition Facts label guidance. Cross-check nutrient amounts against USDA FoodData Central.
Example
A serving with 126 mg of magnesium provides 126 ÷ 420 × 100 = 30% DV (High).
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For informational purposes only; verify against § 101.9(c)(8)(iv). · US Nutrition Label Rules v1.3.0 · CFR snapshot 2026-02-12