Size 4 capsules are among the smallest standard empty capsule sizes commonly used for:
- lower-dose supplements
- concentrated ingredients
- probiotics
- vitamins
- sensitive users
- easier swallowing
Their compact size makes them popular for people who:
- dislike large capsules
- require smaller doses
- prefer lightweight formulations
This guide explains the approximate volume, dimensions, and powder capacity of size 4 empty capsules.
Size 4 Capsule Volume
The approximate internal volume of a size 4 capsule is:
0.21 ml
This smaller internal volume makes size 4 capsules ideal for compact formulations and concentrated powders.
How Many mg Fit in a Size 4 Capsule?
The approximate powder capacity of a size 4 capsule is:
| Powder Type | Approximate Capacity |
|---|---|
| Light powders | 100–130 mg |
| Medium density powders | 150–180 mg |
| Dense powders | 210 mg |
Actual capacity depends on:
- powder density
- particle size
- moisture content
- powder compression
Size 4 Capsule Dimensions
| Measurement | Approximate Size |
|---|---|
| Length | 14.3 mm |
| Diameter | 5.3 mm |
| Volume | 0.21 ml |
Size 4 capsules are smaller than:
- size 3
- size 2
- size 1
- size 0
- size 00
- size 000
making them one of the easiest capsule sizes to swallow.
What Are Size 4 Capsules Used For?
Size 4 capsules are commonly used for:
- probiotics
- concentrated extracts
- vitamins
- low-dose supplements
- herbal powders
- sensitive users
They are often selected when:
- very small capsules are preferred
- swallowing comfort is important
- lower doses are required
Size 4 Capsule Capacity by Powder Density
Different powders can produce different fill weights inside the same capsule.
Low Density Powders
Examples:
- fluffy herbs
- mushroom powders
- botanical powders
Approximate fill:
- 100–130 mg
Medium Density Powders
Examples:
- vitamins
- nutritional blends
- amino acid powders
Approximate fill:
- 150–180 mg
High Density Powders
Examples:
- minerals
- dense extracts
- compact powders
Approximate fill:
- up to 210 mg
Size 4 vs Other Capsule Sizes
| Capsule Size | Approximate Capacity |
|---|---|
| 000 | 700–1400 mg |
| 00 | 500–950 mg |
| 0 | 300–700 mg |
| 1 | 250–500 mg |
| 2 | 180–370 mg |
| 3 | 150–300 mg |
| 4 | 100–210 mg |
Size 4 capsules are considered:
- very small capsules
- suitable for lower dosages
- one of the easiest capsule sizes to swallow
Are Size 4 Capsules Easy to Swallow?
Yes. Size 4 capsules are generally considered very easy to swallow because of their compact dimensions.
They are often preferred for:
- sensitive users
- people who dislike large capsules
- probiotics
- children (where appropriate)
- lower-dose supplements
Gelatin vs HPMC Size 4 Capsules
Size 4 capsules are available in both:
- gelatin capsules
- HPMC vegetarian capsules
Gelatin Capsules
- traditional capsule material
- smooth texture
- commonly used
HPMC Capsules
- vegetarian and vegan friendly
- plant-based
- suitable for clean-label products
Both types have similar capacities and dimensions.
Choosing Size 4 Capsules
Size 4 capsules may be suitable if you want:
- very small capsules
- low powder capacity
- easier swallowing
- compact supplement doses
If your formulation requires larger doses, you may prefer:
- size 3
- size 2
- size 1
- size 0
Frequently Asked Questions
How many mg fit in a size 4 capsule?
Typically around 100–210 mg depending on powder density.
What is the volume of a size 4 capsule?
A size 4 capsule has an approximate volume of 0.21 ml.
Are size 4 capsules easy to swallow?
Yes. Size 4 capsules are among the easiest standard capsule sizes to swallow.
Are vegetarian size 4 capsules available?
Yes. HPMC vegetarian size 4 capsules are widely available.
What are size 4 capsules commonly used for?
They are commonly used for probiotics, vitamins, concentrated supplements, and lower-dose formulations.
Related Pages
- Capsule Sizes Explained
- Capsule Size Chart
- Capsule Volume Chart
- Capsule Capacity Calculator
- Powder Density Calculator
- How Many mg Fit in a Capsule
- Size 000 Capsule Capacity
- Size 00 Capsule Capacity
- Size 0 Capsule Capacity
- Size 1 Capsule Capacity
- Size 2 Capsule Capacity
- Size 3 Capsule Capacity