Capsules are one of the most popular oral dosage forms in the pharmaceutical and nutraceutical industries. However, not all capsules are created equal. The two primary types — hard capsules and softgel capsules — differ fundamentally in their structure, manufacturing process, equipment requirements, and applications. Understanding these differences is essential for choosing the right capsule format and production equipment for your product.

In this article, we'll compare softgel and hard capsule production in detail, helping you make an informed decision for your manufacturing operation.

1. Capsule Structure and Material

Hard Capsules

Hard capsules consist of two separate pieces — a body and a cap — that are pre-manufactured from gelatin or HPMC (hydroxypropyl methylcellulose for vegetarian capsules). The two pieces are supplied empty and are joined together during the filling process. Hard capsules are rigid and available in standard sizes from 000# (largest) to 5# (smallest), with 00# and 0# being the most common for dietary supplements.

The shell material for hard capsules typically contains only gelatin and water, with no plasticizers. This gives them their rigid structure and long shelf stability.

Softgel Capsules

Softgels (soft gelatin capsules) are single-piece, hermetically sealed capsules that are formed, filled, and sealed in a single continuous process. The shell is made from gelatin but contains added plasticizers (typically glycerin or sorbitol) that make it flexible and soft. Softgels can contain liquids, oils, suspensions, or pastes, making them ideal for oil-based active ingredients.

Softgel shells can also include opacifiers, colorants, and flavors. The hermetic seal provides excellent protection against oxidation and moisture, making softgels ideal for sensitive ingredients like fish oil, vitamin E, and coenzyme Q10.

2. Production Process Differences

Hard Capsule Production Process

Hard capsule production is a two-stage process:

1. Capsule shell manufacturing: (Done separately by capsule shell manufacturers) Stainless steel pins are dipped into gelatin solution, dried, and stripped to form the two capsule halves.
2. Capsule filling: The empty capsules are loaded into a capsule filling machine which separates the two halves, fills the body with powder or pellets, rejoins the cap, and ejects the finished capsule.

The filling process for hard capsules is relatively straightforward. Our NJP series machines handle this at rates up to 48,000 capsules per hour. For liquid-filled hard capsules, the specialized NJP-260 fills liquid formulations into two-piece hard capsules.

Softgel Production Process

Softgel production is a single continuous process that is significantly more complex:

1. Gelatin preparation: Gelatin, plasticizer, and water are melted and blended to form the gel mass at controlled temperature (60-70°C).
2. Gel ribbon formation: The gel mass is spread onto cooling drums, forming two continuous gel ribbons.
3. Capsule forming and filling: The two gel ribbons pass between a pair of rotating die rolls. As the dies mesh, injectors pump the fill material (liquid/oil) into the forming capsule cavity.
4. Sealing: The pressure and temperature of the die rolls simultaneously seal the two gel ribbons together, creating the hermetically sealed softgel.
5. Drying: Freshly formed softgels contain excess moisture and are tumble-dried in a series of drying tunnels and rotating drums over 12-24 hours.
6. Finishing: Dried softgels are polished to remove surface oil and inspected for quality.

This entire process requires our RJWJ-100 Softgel Production Line, which integrates the gel preparation, encapsulation, and drying systems into a complete production line.

3. Equipment Requirements

Hard Capsule Equipment

• Manual filler: SL-400 for small batches and labs
• Semi-automatic: DTJ-C or WK-255 for medium production
• Fully automatic: NJP-600/800 or NJP-2000 for large-scale production
• Auxiliary: JFP Capsule Polisher for surface cleaning

Hard capsule equipment is generally less expensive, smaller in footprint, and easier to operate and maintain than softgel equipment.

Softgel Equipment

• Complete production line: RJWJ-100 Softgel Production Line
• Requires gelatin melting tanks, encapsulation machine, drying tunnels, and polishing equipment
• Significantly larger footprint and higher investment
• Requires skilled operators for gel mass preparation and process control
• More complex maintenance and cleaning procedures

4. Fill Material Compatibility

Hard Capsules Can Fill:

• Powders and granules (most common)
• Pellets and beads
• Mini-tablets (multiple in one capsule)
• Liquids (using the NJP-260 liquid filling machine)
• Semi-solid pastes (with specialized dosing)

Softgels Can Fill:

• Liquids and oils (primary application)
• Suspensions (solid particles in oil)
• Pastes and semi-solids
• Concentrated vitamin oils

Softgels cannot effectively fill dry powders alone — the fill must be a liquid or paste that can be injected. Hard capsules are more versatile across different fill material types.

5. Applications and Market Position

Hard Capsules Are Preferred For:

• Dry powder pharmaceutical formulations
• Herbal and botanical supplements in powder form
• Probiotics (moisture-sensitive)
• Products requiring modified-release pellet combinations
• High-dosage dry ingredients
• Budget-conscious production (lower equipment cost)

Softgels Are Preferred For:

• Oil-soluble vitamins (A, D, E, K)
• Fish oil and omega-3 supplements
• Coenzyme Q10 and other lipid-soluble actives
• Products requiring enhanced bioavailability
• Premium nutraceutical positioning
• Products needing protection from oxidation
• Cosmetic and beauty supplements

6. Cost Comparison

Factor	Hard Capsules	Softgels
Equipment Investment	Lower	Higher
Shell Cost	Lower	Higher
Production Speed	Faster	Slower (drying)
Operator Skill	Moderate	High
Maintenance	Simpler	Complex
Consumer Appeal	Standard	Premium

7. Regulatory and Quality Considerations

Both capsule types must meet pharmaceutical regulatory standards, but softgel production involves additional considerations:

• Gel mass control: The gelatin mass must be maintained at precise temperature and viscosity
• Drying validation: Softgel drying process must be validated to ensure final moisture content meets specifications
• Seam integrity: Softgel seals must be tested for hermetic integrity
• Shell thickness: Must be uniform and meet specifications for drug release profiles

For a deeper understanding of regulatory requirements, read our article on GMP requirements for capsule manufacturing.

Conclusion

The choice between hard capsules and softgels depends primarily on your fill material, target market, and production capabilities. If you produce dry powder formulations or need versatile, cost-effective production, hard capsule filling with our NJP series machines is the right choice. If your product is oil-based and you want premium positioning with enhanced bioavailability, the RJWJ-100 softgel line is the answer.

Many manufacturers eventually produce both formats to serve different product lines. Our team can help you evaluate which option best fits your current and future production needs. For help selecting the right machine, see our capsule filling machine buying guide.