There are 13 essential vitamins and 12 essential minerals your body needs to function. The Institute of Medicine and NIH Office of Dietary Supplements publish Recommended Dietary Allowances (RDA) for each, varying by age, sex, and life stage. Our vitamin and mineral calculator surfaces the right RDA values for your situation in one place — vitamins A, C, D, E, K, all 8 B vitamins, plus calcium, iron, magnesium, phosphorus, potassium, sodium, zinc, copper, selenium, iodine, manganese, and chromium. It also adjusts for pregnancy and lactation where the requirements differ.
Provide your age and biological sex.
Toggle if pregnant or lactating for adjusted values.
See daily recommendations for all 13 vitamins and 12 minerals.
RDA values are set to meet the needs of 97-98% of healthy individuals in a given group. Where data is insufficient, the IOM uses Adequate Intake (AI) instead. The Tolerable Upper Intake Level (UL) is the maximum daily amount unlikely to cause harm. Pregnancy and lactation increase requirements for several nutrients (folate, iron, B12, calcium, iodine) — the calculator applies the relevant adjustments.
RDA = NIH/IOM published value for your age + sex + life stage
RDA values cover 97-98% of healthy people — most don't need supplements if eating a varied diet
Common shortfalls in US diets: vitamin D, calcium, magnesium, potassium, fiber
Iron requirements jump from 8 mg (men) to 18 mg (premenopausal women) due to menstrual losses
Pregnancy increases folate, iron, and iodine requirements substantially
Vitamin D is hard to get from food alone — sunlight or supplements often needed
B12 absorption decreases with age — adults over 50 should consider supplementation
Don't exceed Tolerable Upper Intake Levels (UL) — too much of some vitamins can be harmful
Vitamins are essential organic compounds that the body needs in small amounts for hundreds of metabolic processes, from energy production and immune function to bone health and DNA repair. The National Institutes of Health (NIH) publishes Recommended Dietary Allowances (RDAs) that vary significantly by age, sex, and life stage — for example, adult men need 90 mg of vitamin C daily while women need 75 mg, but pregnant women require 85 mg and breastfeeding women need 120 mg. Vitamin D requirements have been a particular focus: the RDA is 600 IU (15 mcg) for adults under 70 and 800 IU (20 mcg) for those over 70, yet surveys show that approximately 42% of US adults are vitamin D deficient. Fat-soluble vitamins (A, D, E, K) are stored in body tissue and can accumulate to toxic levels — the tolerable upper intake for vitamin A is 3,000 mcg RAE, beyond which liver damage risk increases. Water-soluble vitamins (B-complex and C) are excreted in urine, making toxicity rare but also requiring more consistent daily intake. Individual needs diverge further based on diet (vegans need supplemental B12), medical conditions, medications, and lifestyle factors like smoking (which increases vitamin C requirements by 35 mg/day).
Nutrient requirements change dramatically across the lifespan. Children need more calcium per body weight for bone growth. Teenagers need more iron for rapid growth. Premenopausal women need much more iron than men. Pregnancy doubles requirements for several nutrients critical to fetal development. Older adults need more B12 (absorption declines) and more vitamin D (skin synthesis declines). Using a single 'adult' RDA misses these important differences.
Food is almost always preferable to supplements because it provides nutrients in their natural matrix with co-factors and fiber. Supplements have a place — vitamin D for those with limited sun exposure, B12 for vegans and older adults, folate for women of childbearing age, iron for diagnosed deficiency. Beyond these specific cases, taking high-dose supplements 'just in case' has little evidence of benefit and some evidence of harm.
Data sourced from trusted institutions
All formulas verified against official standards.