Capsule sizes run from 000 down to 5, with 000 the largest and 5 the smallest. The chart below gives the dimensions, volume and fill capacity for every size we manufacture.
Capsule size chart
| Size | Closed length (mm) | Cap length (mm) | Body length (mm) | Cap diameter (mm) | Body diameter (mm) | Volume (mL) | Empty weight (mg) |
|---|---|---|---|---|---|---|---|
| 000 | 26.1 | 12.95 | 22.20 | 9.91 | 9.55 | 1.37 | [ ] |
| 00 | 23.4 | 11.80 | 20.22 | 8.56 | 8.23 | 0.90 | [ ] |
| 0 | 21.6 | 10.85 | 18.35 | 7.64 | 7.35 | 0.68 | [ ] |
| 1 | 19.4 | 9.85 | 16.40 | 6.96 | 6.63 | 0.48 | [ ] |
| 2 | 17.6 | 8.80 | 15.15 | 6.39 | 6.12 | 0.36 | [ ] |
| 3 | 15.7 | 8.00 | 13.45 | 5.85 | 5.60 | 0.27 | [ ] |
| 4 | 14.3 | 7.20 | 12.10 | 5.33 | 5.08 | 0.20 | [ ] |
| 5 | 11.1 | 6.20 | 9.30 | 4.91 | 4.68 | 0.13 | [ ] |
Length tolerance ±[ ] mm. Diameter tolerance ±[ ] mm. Empty weight tolerance ±[ ] mg. Measured at [ ]°C and [ ]% RH. Delete any row for a size you do not manufacture.
Fill weight by formulation density
How much powder a capsule holds depends on the bulk density of your mix, not on the capsule alone. Multiply the volume above by your density to get fill weight.
| Size | 0.6 g/mL | 0.8 g/mL | 1.0 g/mL | 1.2 g/mL |
|---|---|---|---|---|
| 000 | 822 | 1096 | 1370 | 1644 |
| 00 | 540 | 720 | 900 | 1080 |
| 0 | 408 | 544 | 680 | 816 |
| 1 | 288 | 384 | 480 | 576 |
| 2 | 216 | 288 | 360 | 432 |
| 3 | 162 | 216 | 270 | 324 |
| 4 | 120 | 160 | 200 | 240 |
| 5 | 78 | 104 | 130 | 156 |
Choosing the right size
Dose
Work out the total mix weight per capsule, active plus excipients, then find the smallest size that holds it. If nothing fits, split the dose across two smaller capsules rather than forcing one large one.
Bulk density
A light, fluffy powder needs a larger capsule than a dense one at the same dose. Measure your tapped bulk density before selecting a size — this is the step most often skipped, and it is the usual cause of a formulation not fitting.
Swallowability
Sizes 00 and 0 are the most widely used because they balance capacity against being comfortable to swallow. For paediatric or veterinary products, size 3 and below are usually preferred.
Gelatin and HPMC
[Describe which you manufacture. Note that both follow the same external dimensions, so machine tooling does not change. Mention your moisture specification for each, since that is what formulators ask about.]
Colours and printing
[List your available colours, whether you offer transparent, and your minimum order quantity for custom colours and axial or radial printing.]
Quality standards
[List the pharmacopoeias you test to — IP, USP, BP, EP — and the tests you run: disintegration, loss on drying, microbial limits, heavy metals. Name your certifications: GMP, ISO, Halal, Kosher. This is the section procurement teams read first.]
Frequently asked questions
What is the length of a size 0 capsule?
A size 0 capsule has a closed length of 21.6 mm and an external cap diameter of 7.64 mm. The cap measures 10.85 mm and the body 18.35 mm.
What is the diameter of a size 00 capsule?
A size 00 capsule has an external cap diameter of 8.56 mm and a body diameter of 8.23 mm. Its closed length is 23.4 mm.
Which capsule size holds 500 mg?
For a powder with a bulk density around 0.8 g/mL, a size 0 capsule holds roughly 544 mg and is the usual choice for a 500 mg fill. A denser mix may fit into a size 1.
What is the largest capsule size?
Size 000 is the largest standard capsule, with a closed length of 26.1 mm and a volume of 1.37 mL.
What is the smallest capsule size?
Size 5 is the smallest standard capsule, with a closed length of 11.1 mm and a volume of 0.13 mL.
Are HPMC capsules the same size as gelatin capsules?
[Answer from your own production data.]
Request a sample
Tell us your fill weight and bulk density and we will recommend a size. Samples available on request.