Daily Iron RDA Calculator
Enter your age, sex, life stage and diet to see the published iron RDA, upper limit and vegetarian or vegan adjustment.
Result
—
Published reference values
— mg iron/day
- Tolerable upper limit
- —
- Vegetarian/vegan adjustment
- —
Safety: Iron overdose is dangerous, especially for children. Supplementation should follow a clinician’s advice after a blood test.
iPhone & iPad · Free
Track it in Iron Tracker.
Track health reference notes and appointments privately on your device.
How much iron per day do you need?
How much iron per day is published for you depends on age, sex and life stage. This calculator reports the supplied NIH Office of Dietary Supplements reference values without recommending supplements or diagnosing deficiency.
For vegetarian and vegan diets, the NIH notes that iron requirements are approximately 1.8 times higher because non-heme iron is less bioavailable. Select that option to see the adjusted figure alongside the published RDA.
Vegetarian or vegan adjustment = published RDA × 1.8 These are published reference values, not a recommendation to supplement. Iron overdose is dangerous, especially for children; supplementation should follow a clinician's advice after a blood test.
Daily iron RDA FAQ
What does the iron RDA mean?
The Recommended Dietary Allowance is the published daily amount for a specified age, sex and life stage. This tool reports the supplied reference values; it does not diagnose deficiency.
Why is the vegetarian or vegan figure higher?
The NIH notes that non-heme iron is less bioavailable, so requirements are approximately 1.8 times higher for vegetarians and vegans.
What is the tolerable upper intake level?
The supplied adult upper limit is 45 mg per day. For children up to age 13, it is 40 mg per day. It is not a target.
Does this calculator recommend an iron supplement?
No. Iron overdose is dangerous, especially for children. Supplementation should follow a clinician's advice after a blood test.
Are my answers saved?
No. The calculation runs in your browser and this tool does not need an account or network call.