Best form of vitamin d.
Forms guide ·3 forms compared ·Reviewed May 2026
For most people, Vitamin D3 (Cholecalciferol) is the vitamin d form to reach for (maintenance, repletion, and general use). Vitamin D2 (Ergocalciferol) is the most budget-friendly option. Calcifediol suits fast repletion and prescription use. There is no single best form for everyone; the right pick depends on your goal, how well you absorb it, and your budget.
The short answer.
A quick, honest verdict. The full side-by-side, with typical doses, is below.
For most people, Vitamin D3 (Cholecalciferol) is the vitamin d form to reach for (maintenance, repletion, and general use). Vitamin D2 (Ergocalciferol) is the most budget-friendly option. Calcifediol suits fast repletion and prescription use. There is no single best form for everyone; the right pick depends on your goal, how well you absorb it, and your budget.
Every form, compared.
Best use, cost tier, and a typical adult dose for each form. The best-for-most pick is a sensible default, not the only good choice.
| Form | Best for | Cost | Typical dose |
|---|---|---|---|
| Vitamin D3 (Cholecalciferol)Best for most | Maintenance, repletion, and general use | Mid | 1000-5000 IU/day |
| Vitamin D2 (Ergocalciferol) | Vegan or prescription-specific use | Budget | 1000-50000 IU as directed |
| Calcifediol | Fast repletion and prescription use | Premium | As prescribed |
Full vitamin d profiles.
Each profile has the evidence, dosing by goal, interactions, and cited sources.
Common vitamin d questions.
Quick answers, drawn from the comparison above.
What is the best form of vitamin d?
Vitamin D3 (Cholecalciferol) is the best vitamin d form for most people (maintenance, repletion, and general use). The right form still depends on your goal, absorption, and budget; see the full comparison for the alternatives.
What is the cheapest form of vitamin d?
Vitamin D2 (Ergocalciferol) is the most budget-friendly form, typically a budget-tier option, with a typical dose of 1000-50000 IU as directed.
How many forms of vitamin d are there?
NutriStack compares 3 commonly sold forms of vitamin d: Vitamin D3 (Cholecalciferol), Vitamin D2 (Ergocalciferol), Calcifediol.
Pick a form, then build your stack
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