What Is a Normal B12 Level?
The normal B12 range is 200–900 pg/mL (optimal >500). Values below or above this range may indicate a condition that requires further evaluation.
Reference Range Table
| Marker | Low | Normal | High |
|---|---|---|---|
| Vitamin B12 | Below 200 pg/mL — deficient | 200–900 pg/mL (optimal >500) | Above 900 pg/mL — typically from supplementation |
What Affects Your Results
Recent B12 supplementation or injections, vegetarian/vegan diet, age (absorption decreases with age), medications (metformin, PPIs), and pernicious anemia (autoimmune B12 malabsorption).
When to Retest
If deficient and supplementing, retest in 8-12 weeks. Once optimal, annually. Vegans and vegetarians should test annually.
Order your B12 test — $8
Order B12