Yes. A fully closed Size 0 capsule can fit inside a Size 000 capsule. Size 000 is substantially larger: our reference dimensions are approximately 26.14 mm locked length and 1.37 mL volume for Size 000, compared with 21.70 mm and 0.68 mL for Size 0. This size relationship can be useful when double encapsulation is required.
Size 0 vs Size 000: Key Dimensions
- Size 000: approximately 26.14 mm locked length, 1.37 mL volume, 9.91 mm cap diameter and 9.55 mm body diameter.
- Size 0: approximately 21.70 mm locked length, 0.68 mL volume, 7.65 mm cap diameter and 7.34 mm body diameter.
- Size order: 000 is larger than 00, and 00 is larger than 0.
Dimensions are reference values and can vary slightly by manufacturer and capsule specification. Check the exact product specification when fit is critical.
What Does “Capsule Inside a Capsule” Mean?
Double encapsulation means placing one fully closed capsule inside a larger outer capsule. A closed Size 0 capsule can be placed inside a Size 000 outer capsule because the outer shell provides sufficient physical space.
- Close the inner Size 0 capsule before inserting it into the Size 000 shell.
- Do not choose the outer capsule by milligram weight alone; physical dimensions determine whether another capsule will fit.
- If you are changing the way a medicine is taken, ask a pharmacist or other qualified healthcare professional first.
Does a Size 0 Filling Machine Work with Size 000 Capsules?
No. A capsule filling machine must match the capsule size it was designed for. A Size 0 filling machine is not a universal machine for Size 000, 00, 1, 2 or other capsule sizes. If you intend to fill both the inner Size 0 and outer Size 000 capsules with a machine, you need equipment compatible with each respective size.
How Does This Compare with Licaps® and DRcaps®?
Capsule compatibility also depends on the specific capsule technology. For example, a Size 0 Licaps® capsule can fit inside a Size 00 or Size 000 DRcaps® outer capsule. A Size 2 DRcaps® is smaller than a Size 0 Licaps®, so it cannot be used as the outer shell for that combination.
Licaps® are intended for suitable oil-based liquid fills; standard DRcaps® are not intended for liquid filling.
Compare All Empty Capsule Sizes
See our Empty Capsule Size Guide for dimensions, volumes and powder-density examples for Sizes 000, 00, 0, 1, 2, 3, 4 and 5. You can also use our Capsule Size Calculator.
Frequently Asked Questions
Can I put a Size 0 capsule inside a Size 000 capsule?
Yes. A fully closed Size 0 capsule can fit inside a Size 000 capsule.
Can a Size 00 capsule fit inside a Size 000 capsule?
Fit depends on the exact capsule specification and intended configuration. Check the physical dimensions of the exact products rather than assuming compatibility from nominal size alone.
Can I use one capsule filling machine for every capsule size?
No. Capsule filling machines are size-specific. The machine and capsule size must match.
Does capsule weight tell me whether one capsule fits inside another?
No. For capsule-within-capsule fitting, physical dimensions are the relevant measurements. For powder filling, volume and bulk density determine approximate weight capacity.
Need help checking a capsule combination? Send us the inner capsule type and size, outer capsule type and size, and what you intend to fill. Browse all empty capsules.
