Free tool · Nutrition
Vitamin B12 intake calculator: how much per day
Short answer
Everyone aged 14 and over needs 2.4 mcg of vitamin B12 a day, rising to 2.6 mcg in pregnancy and 2.8 mcg while breastfeeding. Children need less, from 0.9 mcg at ages 1–3. No upper limit has been set because vitamin B12 has a low potential for toxicity.
Last reviewed 28 October 20261 published sourcesNot medical advice
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Get Reps freeVitamin B12 intake calculator
For anyone aged 1 or over. Infant values are in the table below.
Enter your age to see your vitamin B12 target.
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| Age | Male | Female | Pregnant / breastfeeding |
|---|---|---|---|
| Birth to 6 months | 0.4 mcg* | 0.4 mcg* | — |
| 7–12 months | 0.5 mcg* | 0.5 mcg* | — |
| 1–3 years | 0.9 mcg | 0.9 mcg | — |
| 4–8 years | 1.2 mcg | 1.2 mcg | — |
| 9–13 years | 1.8 mcg | 1.8 mcg | — |
| 14–18 years | 2.4 mcg | 2.4 mcg | 2.6 mcg / 2.8 mcg |
| 19+ years | 2.4 mcg | 2.4 mcg | 2.6 mcg / 2.8 mcg |
Where the numbers come from
The Recommended Dietary Allowances are set by the Food and Nutrition Board and published by the NIH Office of Dietary Supplements. For infants the board set Adequate Intakes instead (NIH ODS: Vitamin B12 fact sheet).
The board did not set an upper limit because of vitamin B12's low potential for toxicity (NIH ODS: Vitamin B12 fact sheet).
Groups more likely to fall short include older adults, people with pernicious anemia or gastrointestinal disorders or surgery, and people who eat little or no animal food (NIH ODS: Vitamin B12 fact sheet).
Fitting it into your diet
Animal foods and fortified foods supply most vitamin B12. If you are building a plant-based plan, check your protein too with the protein calculator.
See what your meals add up to
Reps logs meals by photo, voice or text with a full nutrition breakdown, so you can see how your day's food stacks up.
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Common questions
How much vitamin B12 do adults need?
The RDA is 2.4 mcg a day for men and women aged 14 and over, 2.6 mcg in pregnancy and 2.8 mcg while breastfeeding.
Is there a maximum amount of vitamin B12?
No upper limit was set. The Food and Nutrition Board did not establish one because of vitamin B12's low potential for toxicity.
Who is more likely to run low on vitamin B12?
The fact sheet lists older adults, people with pernicious anemia or gastrointestinal disorders, people who have had gastrointestinal surgery, and people who follow vegetarian or vegan diets.
Sources
Figures on this page were checked against these publications on 28 October 2026.
- Office of Dietary Supplements, National Institutes of Health. Vitamin B12: Fact Sheet for Health Professionals. Updated July 2, 2025. ods.od.nih.gov/factsheets/VitaminB12-HealthProfessional/
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