Vitamin K2 is a fat-soluble vitamin commonly used in bone health, calcium metabolism, and cardiovascular support supplements. It is often combined with Vitamin D3 and delivered in very small doses, meaning capsule fill volumes are usually low compared to many powdered supplements.
Choosing the correct capsule size for Vitamin K2 depends on:
- Whether the ingredient is powder or oil-based
- The dosage strength
- Whether it is blended with other ingredients
- Desired capsule swallowing size
Recommended Capsule Sizes for Vitamin K2
| Capsule Size | Approx Capacity | Best For |
|---|---|---|
| Size 5 | 60–130 mg | Very small Vitamin K2 doses |
| Size 4 | 120–240 mg | K2-only formulations |
| Size 3 | 180–400 mg | K2 with small supporting blends |
| Size 1 | 300–600 mg | K2 combined with D3 or minerals |
| Size 0 | 400–800 mg | Larger wellness blends |
Most standalone Vitamin K2 supplements use:
- Size 4 capsules
- Size 3 capsules
- Softgel-style oil capsules for MK-7 oils
What Is Vitamin K2?
Vitamin K2 helps direct calcium into bones and teeth while helping prevent calcium buildup in arteries. It is commonly available as:
- MK-4
- MK-7
MK-7 is the most popular form due to its longer half-life and lower required dosage.
Vitamin K2 is often paired with:
- Vitamin D3
- Magnesium
- Calcium
- Omega oils
Best Capsule Choice for Vitamin K2
Size 4 Capsules
Best for:
- Pure K2 powder
- Low-dose supplements
- Easy-to-swallow capsules
Typical fill:
- 50–200 mg blends
Size 3 Capsules
Best for:
- K2 + D3 combinations
- Moderate nutrient blends
Typical fill:
- 150–400 mg
Size 1 Capsules
Best for:
- Full bone support formulas
- Multi-ingredient blends
Typical fill:
- 300–600 mg
Gelatin vs Vegetarian Capsules for Vitamin K2
| Capsule Type | Benefits |
|---|---|
| Gelatin Capsules | Cost-effective and widely used |
| HPMC Vegetarian Capsules | Vegan-friendly and moisture stable |
HPMC capsules are especially popular for premium Vitamin K2 supplements.
Vitamin K2 Capsule Filling Tips
- K2 dosages are usually very small, so fillers are commonly added
- Popular fillers include rice flour or microcrystalline cellulose
- Oil-based K2 may require specialized encapsulation or softgels
- Use precise measuring equipment due to low-dose potency
Common Vitamin K2 Supplement Blends
| Blend | Typical Capsule Size |
|---|---|
| Vitamin K2 MK-7 | Size 5–4 |
| Vitamin D3 + K2 | Size 4–3 |
| Calcium + D3 + K2 | Size 1–0 |
| Bone Support Formula | Size 1–00 |
FAQ — Vitamin K2 Capsule Sizes
What is the best capsule size for Vitamin K2?
Size 4 and Size 3 are the most commonly used capsule sizes for Vitamin K2 supplements.
Can Vitamin K2 fit in a Size 5 capsule?
Yes. Because K2 dosages are extremely small, Size 5 capsules are often suitable for concentrated formulations.
Are vegetarian capsules good for Vitamin K2?
Yes. HPMC vegetarian capsules are widely used for Vitamin K2 products.
Is Vitamin K2 usually powder or oil?
Both forms exist. MK-7 is commonly sold in oil-based formulations, while powdered blends are also popular.
Which capsule size is easiest to swallow?
Size 4 and Size 5 capsules are among the easiest capsule sizes to swallow.