Technical Buyer Guide

Empty Capsule Size Guide: How to Choose the Right Capsule Size

Empty hard capsules are available in different standard sizes. Larger capsule numbers do not mean larger capsule volume. Choosing the correct size depends on formulation characteristics, powder density, target fill quantity, filling equipment, and product design. Final size should be confirmed through formulation and filling trials.

Quick Overview

Empty Capsule Sizes Supported by AmgenCapsule

Current standard sizes: 00, 0, 1, 2, 3, and 4. Size decreases as the number increases: 00 is larger than 0, 0 is larger than 1, 1 is larger than 2, 2 is larger than 3, and 3 is larger than 4. There is no universal best size for every formulation.

Size Comparison

Visual Capsule Size Reference

Visual reference only. Use the comparison table below and the full Specifications page for exact dimensions and capacity data.

00#
0#
1#
2#
3#
4#

Capsule Size Chart

Capsule Size Comparison Table

Covering length, outside diameter, and capacity volume are copied from the current Specifications page. Reference fill weights by powder density are available on the full specifications chart.

Listed size data are suitable for Gelatin Empty Capsules and HPMC Empty Capsules. Length and diameter are shown in mm. Capacity is shown in ml.
Capsule Size Covering Length Outside Diameter Capacity Volume
00# 22.2-23.2 mm Cap 8.50-8.58 mm
Body 8.13-8.21 mm
0.95 ml
0# 20.7-21.7 mm Cap 7.57-7.71 mm
Body 7.26-7.40 mm
0.67 ml
1# 18.5-19.5 mm Cap 6.83-6.97 mm
Body 6.56-6.70 mm
0.50 ml
2# 17.0-17.8 mm Cap 6.28-6.42 mm
Body 6.00-6.14 mm
0.37 ml
3# 15.0-15.8 mm Cap 5.76-5.90 mm
Body 5.50-5.64 mm
0.30 ml
4# 13.4-14.3 mm Cap 5.25-5.39 mm
Body 4.98-5.12 mm
0.21 ml

View Full Capsule Size & Capacity Specifications

Formulation Context

Why Powder Density Matters When Choosing Capsule Size

Capsule capacity is a volume measurement. The weight that fits into a capsule varies with the bulk density and physical properties of the filling material. Two powders can occupy the same capsule volume but have different fill weights. Buyers should not select capsule size based only on target milligrams.

Selection Process

How to Choose the Right Empty Capsule Size

Use this process as practical procurement guidance. It does not replace formulation testing or filling trials.

01

Define Target Fill Quantity And Formulation

Confirm the intended fill quantity and formulation characteristics before reviewing capsule capacity.

02

Evaluate Bulk Density And Flow

Assess powder or granule bulk density and flow characteristics that influence how material fills the capsule shell.

03

Compare Required Volume With Capsule Capacity

Match estimated fill volume needs against published capacity for sizes 00 through 4.

04

Confirm Filling Equipment Compatibility

Check whether the intended capsule size aligns with your filling line setup and change parts.

05

Run Filling Trials Before Finalizing Size

Confirm the production size through trial fills rather than relying only on a size chart.

Size Detail

Capsule Size 00

Capsule size 00 is one of the larger sizes in the current AmgenCapsule standard range. It provides higher internal capacity than sizes 0 through 4, with a published capacity volume of 0.95 ml and covering length of 22.2-23.2 mm.

It may be considered when a formulation requires greater volume. Confirm suitability through formulation review and filling trials.

View Empty Capsule Products

Size 00 Snapshot

  • Covering length: 22.2-23.2 mm
  • Capacity volume: 0.95 ml
  • Relative size: Larger than 0, 1, 2, 3, and 4

Size 0 Snapshot

  • Covering length: 20.7-21.7 mm
  • Capacity volume: 0.67 ml
  • Relative size: Smaller than 00; larger than 1–4

Size Detail

Capsule Size 0

Capsule size 0 is smaller than size 00 and larger than sizes 1 through 4. With a published capacity volume of 0.67 ml, it is commonly evaluated when buyers need a balance between capsule volume and product format.

Compare required fill volume, powder density, and equipment compatibility before selecting size 0 over size 00 or size 1.

Smaller Standard Sizes

Capsule Sizes 1, 2, 3, and 4

These sizes provide progressively lower capacity volume within the AmgenCapsule standard range.

Capsule Size 1

Covering length 18.5-19.5 mm. Capacity volume 0.50 ml. Smaller than size 0; larger than sizes 2–4.

Capsule Size 2

Covering length 17.0-17.8 mm. Capacity volume 0.37 ml. Smaller than size 1; larger than sizes 3–4.

Capsule Size 3

Covering length 15.0-15.8 mm. Capacity volume 0.30 ml. Smaller than size 2; larger than size 4.

Capsule Size 4

Covering length 13.4-14.3 mm. Capacity volume 0.21 ml. The smallest size in the current AmgenCapsule standard range.

Material Availability

Are Capsule Sizes the Same for Gelatin and HPMC Capsules?

The current listed size data are suitable for Gelatin Empty Capsules and HPMC Empty Capsules, based on the existing Specifications page. Review material choice separately from size selection.

Gelatin Empty Capsules HPMC Vegetarian Empty Capsules Gelatin vs HPMC Capsules Guide

Production Fit

Check Filling Equipment Compatibility

Capsule filling equipment may use size-specific change parts or settings. Buyers should confirm the intended capsule size against their filling line. Capsule shell type, size, and equipment setup should be checked before bulk ordering.

Procurement Checklist

Capsule Size Selection Checklist

  • Target formulation
  • Target fill quantity
  • Bulk density
  • Powder/granule flow characteristics
  • Required capsule size
  • Filling machine compatibility
  • Capsule material: gelatin or HPMC
  • Color / opacity requirements
  • Printing requirements
  • Trial sample requirements
  • Destination-market requirements

For full dimension and reference fill-weight data, open the Capsule Size & Capacity Specifications page.

Procurement Notes

Common Capsule Size Selection Mistakes

Milligram-Only Selection

Choosing size based only on milligram target.

Ignoring Density

Ignoring powder density when matching fill quantity to capsule volume.

Capacity Equals Fill Weight

Assuming nominal capacity equals guaranteed fill weight.

Equipment Not Checked

Failing to check filling equipment compatibility.

No Trial Fills

Skipping trial fills before confirming production size.

Appearance Before Size

Finalizing color/printing before confirming size.

Reference Weights Misused

Using reference fill weights as guaranteed production values.

FAQ

Frequently Asked Questions

Practical answers for empty capsule size selection.

Which is larger, capsule size 00 or size 0?

Capsule size 00 is larger than capsule size 0. In the AmgenCapsule standard range, size decreases from 00 to 4.

What does capsule size 00 mean?

Capsule size 00 is one of the larger empty hard capsule sizes in the current AmgenCapsule standard range. It has a higher capacity volume than sizes 0, 1, 2, 3, and 4.

How much powder fits in a size 00 capsule?

Size 00 has a published capacity volume of 0.95 ml. Actual fill weight depends on formulation properties and powder bulk density. Use the Capsule Size & Capacity Specifications page for density-based reference fill weights; these are reference values, not guaranteed production fill weights.

How do I choose between size 00 and size 0?

Compare required fill volume with published capacity, then evaluate powder density, product format, and filling equipment. Size 00 provides higher capacity (0.95 ml) than size 0 (0.67 ml). Confirm the final size through formulation and filling trials.

Does capsule fill weight depend on powder density?

Yes. Capsule capacity is a volume measurement. The weight that fits into a capsule varies with bulk density and the physical properties of the filling material.

Are gelatin and HPMC capsules available in the same sizes?

Yes. The current listed size data on the Specifications page are suitable for Gelatin Empty Capsules and HPMC Empty Capsules, covering sizes 00 through 4.

Can capsule size affect filling equipment setup?

Yes. Capsule filling equipment may use size-specific change parts or settings. Confirm the intended capsule size against your filling line before bulk ordering.

Should I run a filling trial before ordering capsules?

Yes. Final capsule size should be confirmed through formulation and filling trials rather than relying only on a size chart or reference fill weights.

Size Selection Support

Need Help Selecting an Empty Capsule Size?

Share your formulation, target fill quantity, powder characteristics, capsule material, and filling equipment requirements. Our team can help identify suitable capsule sizes for further evaluation.