Direct comparison
Hard vs Soft Contact Lenses: RGP Differences
Hard (RGP) vs soft contact lenses side by side: comfort, adjustment time, durability, vision and lifespan, using FDA wording plus CDC hygiene risk.
Written and maintained by CASRAI Editorial Board
Last updated
How do Soft and Hard (rigid gas permeable) compare side by side?
The table below compares Soft and Hard (rigid gas permeable) across 11 dimensions, from name people use to when each fits.
Side-by-side comparison
| Dimension | Soft | Hard (rigid gas permeable) |
|---|---|---|
| Name people use | "Soft" lenses; the same word FDA uses. | "Hard" or "gas permeable" lenses. FDA's page names this type rigid gas permeable (RGP); it does not use the word "hard". |
| Material | Soft, flexible plastics that allow oxygen to pass through to the cornea. Newer soft materials include silicone-hydrogels, which give the eye more oxygen during wear. | Rigid lenses, described by FDA as rigid gas permeable (RGP). |
| Initial comfort | May be easier to adjust to and are more comfortable than RGP lenses. | Not as comfortable initially as soft lenses. |
| Time to get used to them | Several days. | It may take a few weeks. |
| Vision | FDA's page makes no vision-quality claim for soft lenses. | Generally give a clearer, crisper vision. |
| Durability and handling | FDA notes most soft lens wearers get a schedule that calls for frequent replacement. | More durable and resistant to deposit buildup; easier to handle and less likely to tear. |
| How long a lens lasts | Replaced on a frequent or planned schedule. | Last longer than soft lenses. |
| Cost over the life of the lens | FDA's page makes no cost claim for soft lenses. | Tend to be less expensive over the life of the lens because they last longer (FDA wording; no prices are given). |
| Infection risk and hygiene | Failure to wear, clean and store lenses as directed can increase the risk of eye infections such as microbial keratitis (CDC). | The same CDC warning applies to every contact lens wearer; CDC does not compare soft and RGP lenses. |
| Prescription | All contact lenses require a valid prescription (FDA). | All contact lenses require a valid prescription (FDA). |
| When each fits | Fits a wearer who values comfort and a quick adjustment, with the trade-off of regular replacement. The choice and the fitting belong to a licensed eye care practitioner. | Fits a wearer who values durability, crisp vision and long lens life, with the trade-off of a slower start. The choice and the fitting belong to a licensed eye care practitioner. |
Sources
- FDA, Types of Contact Lenses (page current as of 01/16/2018), read 2026-10-30
- CDC, Contact Lens Healthy Habits (dated 2025-05-27), read 2026-10-30
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Common questions
Common questions about Soft vs Hard (rigid gas permeable)
Are hard contact lenses the same as gas permeable lenses?
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"Hard" is an everyday term. The FDA's Types of Contact Lenses page describes the rigid type as rigid gas permeable (RGP) lenses, so searches for hard and for gas permeable lenses point to the same comparison with soft lenses.
Which are more comfortable at first, hard or soft lenses?
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Soft lenses. FDA states soft lenses may be easier to adjust to and are more comfortable than RGP lenses, and that RGPs are not as comfortable initially.
Which lasts longer, hard or soft contact lenses?
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RGP lenses. FDA says they last longer than soft lenses and are more durable, while most soft lens wearers get a schedule calling for frequent replacement.
Do I need a prescription for either type?
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Yes. FDA states that all contact lenses require a valid prescription. This page is general product information, not medical advice.
Going deeper
