Typical reference ranges
| Level (ng/mL) | nmol/L | NIH / IOM view | Many lab reports |
|---|---|---|---|
| Below 12 | Below 30 | Deficient | Deficient |
| 12–19 | 30–49 | Inadequate for some people | Deficient |
| 20–29 | 50–74 | Adequate for most | Insufficient |
| 30–50 | 75–125 | Adequate | Sufficient |
| 50–150 | 125–375 | Possible adverse effects; more concern above 60 | Sufficient up to 100, then often flagged high |
| Above 150 | Above 375 | Toxicity: marked high calcium | Toxic |
Ranges based on: MedlinePlus; NIH Office of Dietary Supplements; Endocrine Society 2024 guideline. Full references are listed at the end of this page.
Use your own lab's range. Reference ranges differ between labs, analysers and methods, and with age, sex and pregnancy. The range printed on your report takes priority over the figures here.
Check your value
Type the 25-OH vitamin D result from your report to see where it sits against the typical ranges on this page. Nothing is sent or saved.
General information only, not a diagnosis. Your lab's printed range takes priority.
Why guidelines disagree
Bodies that focus on bone health for the general population (the US Institute of Medicine, NIH and the UK SACN, which uses 25 nmol/L or 10 ng/mL as its deficiency threshold) set lower cut-offs. Older clinical guidance aimed at people with osteoporosis or other conditions set 30 ng/mL as a target, and many labs still print that. Your doctor will interpret your result for your situation.
Why deficiency is so common in Pakistan, India and the Gulf
Darker skin needs more sun to make vitamin D, and covered clothing, indoor work, air pollution and avoiding midday heat all reduce exposure. Studies in South Asia and the Gulf report low levels in a large share of adults, especially women.
Symptoms
Many people have no symptoms. Severe deficiency can cause bone pain, muscle weakness, rickets in children and osteomalacia in adults.
Too much vitamin D
Toxicity almost always comes from high-dose supplements or injections, not from sun or food. It raises blood calcium, causing thirst, nausea, confusion and kidney problems. Large injected doses, common in some countries, should only be used under medical advice.
Frequently asked questions
What is a normal vitamin D level?
20 ng/mL (50 nmol/L) or more is adequate for most people by NIH standards; many labs call 30–100 ng/mL sufficient.
How do I convert ng/mL to nmol/L?
Multiply by 2.5. 20 ng/mL is 50 nmol/L.
Do I need to fast for a vitamin D test?
No.
How long does it take to raise vitamin D?
Levels usually rise over 2–3 months of regular supplements; re-testing is often done after about 3 months.
Sources and references
- MedlinePlus: Vitamin D Test
- NIH Office of Dietary Supplements: Vitamin D fact sheet
- Endocrine Society 2024 guideline: Vitamin D for the prevention of disease