Enter your 25-hydroxyvitamin D (25(OH)D) result and see whether it's deficient, insufficient, or sufficient — computed instantly in your browser, nothing sent anywhere.
Vitamin D is measured, not calculated, from a 25(OH)D blood test. The Endocrine Society's 2011 guideline defines under 20 ng/mL as deficient, 20–29 ng/mL as insufficient, and 30 ng/mL or above as sufficient. Many labs print a wider "normal" range on the report, but a result inside that range can still sit in the deficient or insufficient zone by this guideline.
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Deficient and insufficient follow the Endocrine Society's 2011 Vitamin D Clinical Practice Guideline (deficiency below 20 ng/mL, insufficiency 20–29 ng/mL, sufficiency 30 and above). The lowest tier, below 10 ng/mL (25 nmol/L), also falls under the 12 ng/mL level the US Institute of Medicine links to deficiency. There is no coded upper "toxicity" cutoff here deliberately — your lab's own high flag or your clinician should confirm toxicity risk at unusually high levels.
| Category | 25(OH)D (ng/mL) | 25(OH)D (nmol/L) |
|---|---|---|
| Severely deficient | Below 10 | Below 25 |
| Deficient | 10–19.9 | 25–49.9 |
| Insufficient | 20–29.9 | 50–74.9 |
| Sufficient | 30 or above | 75 or above |
Yes. 32 ng/mL (about 80 nmol/L) is sufficient by every current standard. It clears the 30 ng/mL line in the Endocrine Society's 2011 guideline, which is where FixFirst flags, and the 20 ng/mL the US Institute of Medicine treats as adequate for bone health. The Endocrine Society's 2024 update set no target level and suggests against routine 25(OH)D testing.
At 32 there is no case for a high-dose supplement. If you already take a daily maintenance dose, keep it. Some longevity voices aim for 40–60 ng/mL (Rhonda Patrick and Bryan Johnson cite that range; see borderline results). That is their target, not a guideline's, and the NIH Office of Dietary Supplements links levels above 50 ng/mL to potential adverse effects. For symptoms and causes at lower levels, see low vitamin D.
A direct walk-through of the conversion and what the guideline says at this level.
ng/mL = nmol/L ÷ 2.496
9.6 ng/mL falls below 10 ng/mL, the calculator's lowest tier, and under both the Endocrine Society's 20 ng/mL deficiency line and the 12 ng/mL level the US Institute of Medicine links to deficiency. At this level, prescription-dose repletion is usually the appropriate next step rather than a standard over-the-counter dose — this is a see-your-doctor-within-a-week situation, not one to self-treat.
Once repletion is underway and levels start rising, an ongoing maintenance dose is commonly in the range of 2,000–4,000 IU of vitamin D3 daily, taken with a fat-containing meal to help absorption. Levels typically rise meaningfully within 8–12 weeks of consistent dosing, which is when a retest makes sense; mood, energy, and sleep quality can start to improve within 4–8 weeks.
References & Guidelines
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