Free Nutrition Calculator

Daily Vitamin & Mineral Calculator

Find your recommended daily intake (RDA) of all key vitamins and minerals based on your age and gender. Based on WHO and NIH guidelines.

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Most important vitamins & minerals

D

Vitamin D — the sunshine vitamin

Most people are deficient in vitamin D, especially in northern latitudes. Essential for calcium absorption, immune function, and mood regulation. Fatty fish, fortified dairy, and sunlight are primary sources.

B12

Vitamin B12 — critical for vegans

Found almost exclusively in animal products. Deficiency causes anaemia and neurological damage. Vegans and vegetarians should supplement B12 or eat B12-fortified foods regularly.

Fe

Iron — especially important for women

Women of reproductive age need significantly more iron than men due to menstrual losses. Iron deficiency is the world's most common nutrient deficiency. Red meat, legumes, and dark leafy greens are top sources.

Mg

Magnesium — the relaxation mineral

Involved in 300+ enzymatic reactions. Supports sleep, muscle recovery, and stress response. Commonly under-consumed. Best sources: dark chocolate, nuts, seeds, leafy greens, and whole grains.

Where these RDA values come from

The values shown here are Recommended Dietary Allowances (RDAs) and Adequate Intakes (AIs) established by the U.S. National Academies of Sciences, Engineering, and Medicine's Food and Nutrition Board, in coordination with guidance from the WHO. These figures represent the daily intake level sufficient to meet the nutrient needs of nearly all (97–98%) healthy individuals in a given age and gender group — they are deliberately set with a safety margin above the average person's actual minimum requirement.

These are general population guidelines, not a personalised prescription. People with malabsorption conditions (like celiac disease or Crohn's), those on restrictive diets, older adults, and pregnant or breastfeeding women often have different needs than the standard RDA reflects. Blood testing is the only reliable way to confirm an actual deficiency — this calculator is meant to help you understand general targets, not replace lab work or a doctor's advice, especially before starting any high-dose supplementation.

Frequently asked questions about vitamins & minerals

For most healthy adults eating a varied diet, large studies have found little evidence that multivitamins meaningfully reduce disease risk or improve outcomes. They can be useful as insurance for specific gaps (like vitamin D in winter, or B12 for vegans) rather than as a blanket recommendation for everyone.
Yes, especially with fat-soluble vitamins (A, D, E, K) which are stored in the body rather than excreted like water-soluble ones (vitamin C, B vitamins). Excess vitamin A, for example, can be toxic at high doses. This is generally only a concern with supplements, not food — it's very difficult to overdose on vitamins from diet alone.
The only reliable way is a blood test ordered by a doctor. Symptoms like fatigue, hair loss, or brittle nails are often blamed on vitamin deficiencies but can have many other causes, so it's worth getting tested rather than self-diagnosing and supplementing based on symptoms alone.
Generally yes, where practical — whole foods provide vitamins alongside fibre, other nutrients, and compounds that may work synergistically, and it's harder to overdose from food. Supplements are most useful for specific, hard-to-get-from-diet nutrients (like B12 for vegans, or vitamin D in low-sunlight regions) rather than as a general replacement for a varied diet.

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