Capsule sizes run from the large size 000 down to the tiny size 5, and the numbers are not intuitive: the bigger the number, the smaller the capsule. This chart shows the volume, approximate length and how much powder each size typically holds, so you can pick the right one for your product.
Size 0 and size 1 are the most common sizes for supplements and medicines. Size 00 suits larger doses, size 000 is rarely used for oral products, and sizes 3 to 5 suit small doses or capsules for children and pets.
Empty capsule size chart
| Size | Volume (ml) | Closed length (mm) | Fill at 0.8 g/ml (mg) |
|---|---|---|---|
| 000 | 1.37 | 26.1 | ≈ 1,100 |
| 00 | 0.91 | 23.3 | ≈ 730 |
| 0 | 0.68 | 21.7 | ≈ 545 |
| 1 | 0.50 | 19.4 | ≈ 400 |
| 2 | 0.37 | 18.0 | ≈ 295 |
| 3 | 0.30 | 15.9 | ≈ 240 |
| 4 | 0.21 | 14.3 | ≈ 170 |
| 5 | 0.13 | 11.1 | ≈ 105 |
Values are typical industry figures and vary slightly between manufacturers. “Elongated” versions such as 00el and 0el hold a little more than the standard size.
How to work out the fill weight for your powder
The weight a capsule holds depends on how dense your powder is. Multiply the capsule volume by the powder’s tapped density:
Fill weight (mg) = Capsule volume (ml) × Powder density (g/ml) × 1000
For example, a size 0 capsule (0.68 ml) filled with a powder of 0.6 g/ml holds about 0.68 × 0.6 × 1000 ≈ 408 mg. The same capsule filled with a denser powder of 1.0 g/ml holds about 680 mg. Light, fluffy herbal powders need a bigger size than dense mineral powders for the same dose.
Which size should you choose?
Size 00 and 0
Larger single doses of herbal extracts, protein-type supplements and multi-ingredient formulas. Size 0 is the best-selling size worldwide.
Size 1 and 2
Standard medicines and supplements with moderate doses. They are easier to swallow and popular for daily-use products.
Size 3, 4 and 5
Small, potent doses, clinical trial blinding, and products for children or animals where a small capsule is easier to give.
Tips for choosing
- Test-fill first. Fill a few capsules by hand or on your machine to confirm the real weight with your powder.
- Think about swallowing. If two capsules of a smaller size give the same dose, they may be easier for many people to swallow than one size 00.
- Match your machine. Filling machines use change parts for each size, so check which sizes your equipment supports.
- Choose the shell material. Decide between gelatin and HPMC early, as it affects cost, stability and your label.
Frequently asked questions
What is the most common capsule size?
Size 0 is the most widely used size, followed by size 1 and size 00.
How many mg does a size 0 capsule hold?
Typically about 400–700 mg, depending on the density of the powder. At an average density of 0.8 g/ml it holds about 545 mg.
Is size 000 bigger than size 00?
Yes. Size 000 is the largest standard size, holding about 1.37 ml, but it is too large for many people to swallow comfortably.
Need empty capsules in a specific size?
Soft Enterprises supplies empty hard gelatin and HPMC capsules in common sizes and colours, in bulk. Send us your size, colour and quantity.
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