In pharmaceuticals and dietary supplements, capsule size matters more than you think. The right capsule size affects dosage accuracy, user experience, and even manufacturing efficiency.
Capsules are numbered by size. The larger the number, the smaller the capsule. Size 000 is the largest standard capsule. Size 5 is the smallest. This guide will help you understand each size’s dimensions, volume, and fill weight.
1.Capsule Size Chart: Dimensions and Capacities
Here is a complete size comparison chart:
*Fill weight depends on powder density (typically 0.6 - 1.2 g/ml)
A size 0 capsule is about the size of a jellybean. Size 000 is almost the length of a quarter.
2.Understanding Capsule Size Numbering
Numbering Logic
The capsule sizing system works backward: higher numbers mean smaller capsules. Size 000 is large and ideal for high dosages. Size 5 is very small, best for minimal quantities or child-friendly formulations.
Common Sizes in Use
- Size 00: Popular in supplements due to high volume and easy swallowing.
- Size 0: A common choice for moderate-dose applications.
- Size 1: Widely used in pharmaceuticals for easy swallowing and moderate volume.
3.Capsule Volume and Fill Weight Considerations
Bulk Density Impact
Capsule capacity is not just about volume. It also depends on the density of the fill material. Light powders fill less per capsule. Dense powders allow more mg per capsule.
Calculation Examples
- A size 00 capsule filled with a powder of 0.8 g/ml density holds approx. 760 mg.
- A size 1 capsule with a powder of 1.0 g/ml fills about 500 mg.
Tip: Always test fill weights with your actual material before production.
4.Capsule Materials: Gelatin vs. Vegetarian Options
Material Types
- Gelatin: Traditional, cost-effective, suitable for most applications.
- HPMC (Hydroxypropyl Methylcellulose): Plant-based, non-GMO, heat-tolerant.
- Pullulan: Natural, biodegradable, offers excellent oxygen barrier.
Use Cases
- Use HPMC or Pullulan for vegan or religious dietary restrictions.
- Use Gelatin where cost-efficiency and rapid dissolution are important.
5.Selecting the Right Capsule Size for Your Needs
Factors to Consider
- Dosage: High-dose requires larger capsules.
- Ease of Swallowing: Children and older adults prefer smaller capsules.
- Fill Type: Dense powders vs. light powders affect capacity.
- Machine Compatibility: Ensure your filling equipment supports the selected size.
Decision-Making Tips
- For supplements: Start with size 00 or 0.
- For pharmaceutical capsules: Size 1 is a good general choice.
- For sensitive markets (children, elderly): Size 3 or 4 might be better.
6.Capsule Filling Machines and Compatibility
Machine Types
- Manual Capsule Fillers: Best for small batches and labs.
- Semi-Automatic Machines: Mid-range production, more control.
- Automatic Machines: For large-scale manufacturing.
Size Compatibility
Not all machines support all sizes. Most support sizes 000 to 4. Always confirm the size range with the manufacturer.
7.Frequently Asked Questions (FAQs)
What is the smallest capsule size available?
Size 5 is the smallest standard size. It holds about 60 to 130 mg depending on the powder.
How many milligrams can fit into a Size 00 capsule?
Between 600 to 1100 mg depending on powder density.
Are Size 00 capsules larger than Size 0?
Yes. Size 00 is longer and has a greater volume than Size 0.
Can I use the same capsule size for different types of fill materials?
Yes, but your fill weight will vary. Always test for volume and compaction.
Understanding capsule sizes helps you ensure accurate dosing, better user experience, and smooth production. From size 000 to size 5, each has specific use cases depending on your needs.
Choose capsules based on your formula, your target audience, and your machine setup. Don’t forget to check fill tests and equipment specs.