Size 00 Empty Capsules in Bulk: Capacity, Uses and Choosing Gelatin vs HPMC
Size 00 is one of the most widely used capsule sizes for adult dietary supplements. It holds a typical volume of about 0.91 mL, which is enough for many 500–700 mg powder doses while staying swallowable for most adults. This guide from Capsules Hub Inc., a US supplier of bulk empty capsules in Islandia, NY, […]
Size 00 is one of the most widely used capsule sizes for adult dietary supplements. It holds a typical volume of about 0.91 mL, which is enough for many 500–700 mg powder doses while staying swallowable for most adults. This guide from Capsules Hub Inc., a US supplier of bulk empty capsules in Islandia, NY, explains size 00 capacity, typical uses and how to choose between gelatin and HPMC shells.
Key takeaways
- A size 00 capsule has a typical volume of about 0.91 mL and a closed length of about 23.3 mm.
- Fill weight = volume × tapped density: roughly 546 mg at 0.6 g/mL and 728 mg at 0.8 g/mL.
- Choose gelatin for most powder fills where an animal-derived shell is acceptable; choose HPMC for vegan claims or moisture-sensitive actives.
- Capsules Hub supplies size 00 in Halal-certified bovine gelatin, HPMC, enteric coated and custom colour versions, in bulk cartons only.
What are the dimensions of a size 00 capsule?
A standard size 00 two-piece hard capsule has a typical volume of about 0.91 mL, a closed length of about 23.3 mm, a cap diameter of about 8.53 mm and a body diameter of about 8.18 mm. These are typical industry figures; the exact dimensions and tolerances for the capsules you buy are on the supplier’s specification sheet.
For comparison with neighbouring sizes, see the table below or the full empty capsule size chart.
| Size | Typical volume (mL) | Approx. fill at 0.6 g/mL (mg) | Approx. fill at 0.8 g/mL (mg) |
|---|---|---|---|
| 000 | 1.37 | 822 | 1,096 |
| 00 | 0.91 | 546 | 728 |
| 0 | 0.68 | 408 | 544 |
| 1 | 0.50 | 300 | 400 |
How much powder fits in a size 00 capsule?
Roughly 550–730 mg for most supplement powders, depending on tapped density. The calculation is simple: fill weight (mg) ≈ capsule volume (mL) × tapped density (g/mL) × 1,000.
- At 0.6 g/mL: about 546 mg per capsule.
- At 0.8 g/mL: about 728 mg per capsule.
- At 1.0 g/mL: about 910 mg per capsule.
Real fill weights also depend on powder flow, compaction and your filling machine. Filling close to the theoretical limit can make capsules harder to close consistently, so leave some headroom and confirm with a pilot run. Our guide on how to choose the right capsule size walks through the method step by step.
What is a size 00 capsule used for?
Size 00 is typically used for adult supplements where the dose is too large for a size 0 but a size 000 would be harder to swallow. It is a common middle ground for brands that want fewer capsules per serving.
Typical applications include:
- Botanical and herbal powder blends with moderate density.
- Vitamin and mineral formulations with higher milligram doses.
- Multi-ingredient blends where the total fill exceeds what a size 0 holds (about 0.68 mL).
- Probiotic, enzyme and moisture-sensitive formulas, often in HPMC or enteric coated shells.
If your dose only half-fills a size 00, a smaller size or a denser blend usually gives a more consistent fill weight.
Should I choose size 00 or size 0?
Choose the smallest size that holds your dose with some headroom. If your fill needs more than about 0.68 mL, size 0 will not fit and size 00 is the next step up.
For example, a 500 mg dose at a tapped density of 0.6 g/mL needs about 0.83 mL. That fits in a size 00 (0.91 mL) but not a size 0. Also consider swallowability for your end users and the change parts available for your encapsulator, since each size usually needs its own tooling.
Gelatin or HPMC for size 00 capsules?
Gelatin suits most powder and granule fills when an animal-derived shell is acceptable; HPMC suits vegan and clean-label products and moisture-sensitive actives. Both are available in size 00.
| Factor | Gelatin (bovine) | HPMC (hypromellose) |
|---|---|---|
| Source | Animal collagen | Plant cellulose |
| Typical shell moisture | About 13–16% | Typically 3–7% |
| Label positioning | Halal when the gelatin is certified | Vegan and vegetarian |
| Hygroscopic fills | Shell water can migrate into the fill | Lower moisture helps protect the fill |
| Unit cost | Usually lower | Usually higher |
Capsules Hub gelatin capsules are made from Halal-certified bovine gelatin and are available in sizes 000 to 4. HPMC capsules are plant-based and also available in 000 to 4. For a deeper comparison, read gelatin vs HPMC capsules: how manufacturers choose.
Are enteric coated and custom colour size 00 capsules available?
Yes. Capsules Hub offers enteric coated capsules in sizes 00 to 3 on a gelatin or HPMC base, and custom colour options on all materials.
Enteric coated shells are designed to resist stomach acid and release in the small intestine, which can suit probiotics, enzymes and other acid-sensitive actives. Custom colour options include Pantone matching, two-tone cap and body, opaque or transparent shells, pearl finishes and radial printing. You can sketch a combination with the capsule builder.
How should bulk size 00 capsules be stored?
Keep cartons sealed in a controlled room, typically around 15–25 °C and 35–65% relative humidity, and always follow the storage conditions on the product specification. Gelatin shells are the most sensitive to humidity changes. See storing and handling empty capsules in bulk for more detail.
Frequently asked questions
How many milligrams does a size 00 capsule hold?
It depends on powder density. A size 00 capsule has a typical volume of about 0.91 mL, so it holds roughly 546 mg at a tapped density of 0.6 g/mL and about 728 mg at 0.8 g/mL. Confirm your actual fill weight with a pilot run.
Is size 00 the same in gelatin and HPMC?
Both materials are made to the same standard size designations, and Capsules Hub supplies gelatin and HPMC capsules in size 00. Exact dimensions and tolerances for each product are on the specification sheet sent with your quote.
Can I get enteric coated or coloured size 00 capsules?
Yes. Enteric coated capsules are available in sizes 00 to 3 on a gelatin or HPMC base, and custom colours, two-tone shells, pearl finishes and radial printing are available on all materials.
Do you sell small packs of size 00 capsules?
No. Capsules Hub supplies empty capsules in bulk cartons only, to manufacturers who fill their own formulations.
How do I request a bulk quote?
Send your capsule type, size, colour, approximate quantity, delivery location, timeline and the documents your QA team needs through the Capsules Hub bulk quote form. Tell us you need size 00, the shell material and colour, and we will reply with bulk pricing and availability. If you are unsure whether size 0 or 00 fits, include your fill weight and tapped density.
Capsules Hub Inc. is a US-based supplier of empty two-piece hard capsules, located at 85 Hoffman Lane, Unit W, Islandia, NY 11749. Call 631-819-0355 or email sales@capsuleshub.us. We supply bulk cartons to manufacturers only; we do not sell retail packs.
Sourcing empty capsules for your next production run? Tell us the type, size and quantity and we will reply with bulk pricing and availability.
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