This capsule sizes chart compares standard empty capsule sizes 000, 00, 0, 1, 2, 3, 4 and 5 by dimensions, volume and approximate fill weight. Size 000 is the largest standard human capsule in our range and size 5 is the smallest. Capsule capacity is determined by volume and powder bulk density, so the same milligram weight can require different capsule sizes.
Empty Capsule Size & Specification Table
The table below uses our capsule specification data. Fill weights are approximate and depend on powder bulk density and filling characteristics.
| Specification | 000 | 00 | 0 | 1 | 2 | 3 | 4 | 5 |
|---|---|---|---|---|---|---|---|---|
| Fill weight @ 0.45 g/mL (mg) | 615 | 430 | 305 | 225 | 165 | 135 | 95 | 60 |
| Fill weight @ 0.70 g/mL (mg) | 960 | 665 | 475 | 350 | 260 | 210 | 145 | 90 |
| Fill weight @ 1.00 g/mL (mg) | 1370 | 950 | 680 | 500 | 370 | 300 | 210 | 130 |
| Volume (mL) | 1.37 | 0.95 | 0.68 | 0.50 | 0.37 | 0.30 | 0.21 | 0.13 |
| Locked length (mm) | 26.14 | 23.30 | 21.70 | 19.40 | 18.00 | 15.90 | 14.30 | 11.10 |
| External diameter — Cap (mm) | 9.91 | 8.53 | 7.65 | 6.91 | 6.35 | 5.82 | 5.31 | 4.91 |
| External diameter — Body (mm) | 9.55 | 8.18 | 7.34 | 6.63 | 6.07 | 5.56 | 5.05 | 4.68 |
| Cap cut length (mm) | 12.95 | 11.74 | 10.72 | 9.78 | 8.94 | 8.06 | 7.33 | 6.20 |
| Body cut length (mm) | 22.20 | 20.22 | 18.44 | 16.61 | 15.27 | 13.59 | 12.19 | 9.32 |
| Average shell weight (mg) | 163 | 118 | 95 | 76 | 61 | 48 | 38 | 28 |
Dimensions and fill weights are reference values. Always check the specification of the exact capsule product before production.
Empty Capsule Sizes: 000 to 5
| Size | Approx. volume | Typical guide fill range* | Relative size |
|---|---|---|---|
| 000 | ~1.37 mL | 800-1600 mg | Largest |
| 00 | ~0.95 mL | 600-1100 mg | Very large |
| 0 | ~0.68 mL | 400-800 mg | Large |
| 1 | ~0.50 mL | 300-500 mg | Medium |
| 2 | ~0.37 mL | 200-400 mg | Medium-small |
| 3 | ~0.30 mL | 150-300 mg | Small |
| 4 | ~0.21 mL | 120-240 mg | Very small |
| 5 | ~0.13 mL | 78-156 mg | Smallest |
*Fill weights are approximate guides only. Actual capacity depends strongly on bulk density, particle size and how tightly the powder is packed.
Why 500 mg Does Not Always Mean the Same Capsule Size
Capsules hold a volume, not a fixed weight. A dense powder may fit 500 mg into a smaller capsule while a light botanical powder may require a larger shell for the same weight. If your ingredient specification provides bulk density in g/mL, multiply the capsule volume by the bulk density to estimate fill weight.
Which Size for Herbal Powders?
Herbal powders vary widely in density. Sizes 00 and 0 are common starting points, but the correct choice should be tested with the actual powder. Browse our empty capsule range.
Which Size for Probiotic or Enzyme Powder?
The same density rule applies to probiotic and enzyme powders. If delayed release is part of your formulation goal, compare sizes in our DRcaps delayed-release capsule range. Also read Do Probiotics Survive Stomach Acid?.
Which Size for a Tablet or Another Capsule?
If you want to place an existing tablet or smaller capsule inside a larger empty shell, use physical dimensions rather than tablet weight. Size 000 provides the most internal space in the standard human range. Always check with a pharmacist or other qualified healthcare professional before changing how a medicine is taken.
Small Capsules: Size 4 and Size 5
Sizes 4 and 5 are useful when only a small quantity is required or when a smaller shell is preferred. They are also frequently considered for pet applications. For medicines, ask a veterinarian or pharmacist before re-encapsulating or dividing a dose. See our guide to empty capsules for cats and dogs.
Gelatin, HPMC, Pullulan or DRcaps?
Size is only one part of the choice. Shell material and release profile also matter. Compare the main options in our Empty Capsule Types Compared guide.
Detailed Guides for Each Capsule Size
For more detail on capacity, typical fill ranges and size comparisons, see our individual guides:
- Size 000 Empty Capsule Guide
- Size 00 Empty Capsule Guide
- Size 0 Empty Capsule Guide
- Size 1 Empty Capsule Guide
- Size 2 Empty Capsule Guide
- Size 3 Empty Capsule Guide
- Size 4 Empty Capsule Guide
- Size 5 Empty Capsule Guide
Frequently Asked Questions
Is size 000 bigger than size 00?
Yes. Size 000 is larger than 00, which is larger than 0. Sizes then become progressively smaller from 1 through 5.
What capsule size holds 500 mg?
There is no universal answer because 500 mg of one powder can occupy a very different volume from 500 mg of another. Bulk density is the key measurement.
What is the smallest empty capsule?
Size 5 is the smallest standard human two-piece capsule size in our range.
What is the largest empty capsule?
Size 000 is the largest standard human two-piece capsule size in our range.
Ready to choose? Browse all empty capsules or contact Pure Capsules with your ingredient, target fill weight and bulk density for help with physical size selection.
