Capsule Size Chart — Choose the Right Size for Your Fill

Capsule sizes run from 000 (largest) down to 4 — the bigger the number, the smaller the capsule. Size selection = target fill weight ÷ bulk density of your fill → the smallest capsule whose volume covers it. Example: 500 mg at 0.7 g/mL bulk density needs ~0.71 mL → size 0.

Capsule Size Chart (two-piece hard capsules, nominal volumes)

Size	Nominal volume mL	Fill @0.5 g/mL	@0.7 g/mL	@1.0 g/mL
000	1.37	685 mg	959 mg	1,370 mg
00	0.95	475 mg	665 mg	950 mg
0	0.68	340 mg	476 mg	680 mg
1	0.50	250 mg	350 mg	500 mg
2	0.37	185 mg	259 mg	370 mg
3	0.30	150 mg	210 mg	300 mg
4	0.21	105 mg	147 mg	210 mg

Volumes are industry-nominal; actual fill weight = volume × your formulation bulk density, affected by compressibility and particle size. Confirm with a filling trial — 1,000 or 5,000 sample capsules on your fill.

Size Selection in Three Steps

1. Define the target fill weight (mg) from active dose plus excipients.
2. Measure bulk density (g/mL) — a 0.1 g/mL swing can move you a full size.
3. Pick the smallest size whose volume covers the need; verify capsule outer diameter against your filling tooling.