Health
Vitamin D Calculator
🔒 Runs in your browser
Estimate your daily vitamin D needs based on age, sun exposure, and diet. See how much you get from each source and whether you need a supplement.
StatusLikely sufficient
From sun
400
IU/day
From diet
300
IU/day
RDA target
600
IU/day
Natural intake meets RDANo supplement needed
Your sun and diet intake may meet your daily needs. Still consider a supplement in winter months or if you live at high latitude.
Estimates based on NIH / Endocrine Society guidelines. Sun synthesis varies with skin tone, latitude, and season. Consult a healthcare provider before starting supplements.
How Much Vitamin D Do You Need? (2026)
How Much Vitamin D Do You Need? — free online tool and guide with examples.