Vitamin D Dosage by Blood Level Calculator
Enter your 25(OH)D blood test result and the level you're aiming for. Get a suggested daily IU dose to close the gap, plus a clear flag if that dose is unusually high. Nothing uploaded.
25(OH)D ?
ng/mL / nmol/L toggle
Suggested daily IU dose
High-dose safety flag
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Results
-Current → target
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Suggested daily dose
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Based on a commonly cited rule of thumb (~100 IU/day raises 25(OH)D by ~1 ng/mL), which varies by body weight, sun exposure, absorption, and starting level. Informational only, not medical advice - discuss results with a doctor before starting or changing a supplement dose.