Silicone Hydrogel vs Hydrogel Contact Lenses: What's the Difference and Which Is Right for You?
31st Aug 2026
If you wear soft contact lenses, chances are they're made from either hydrogel or silicone hydrogel. At first glance, that might not sound like a big deal — both materials are soft, flexible, and designed to correct your vision. But the material behind your lenses affects things like how much oxygen reaches your eye, how much water the lens holds, how it's designed, and how it sits on your eye's surface. So, is silicone hydrogel the better choice? Not necessarily. Silicone hydrogel lenses generally let a lot more oxygen through to the cornea than traditional hydrogel lenses do. But that doesn't automatically mean they're more comfortable, or the right fit for every wearer. The best lens for you comes down to more than just the material. Your prescription, how well the lens fits, your tear film, how often you replace your lenses, and the specific lens design all play a part in how well it works for your eyes.
Hydrogel vs silicone hydrogel: the quick answer
Here's the difference in plain terms: Hydrogel lenses use the water held within the lens to carry oxygen to the cornea. Silicone hydrogel lenses have silicone built into the material, which lets significantly more oxygen pass through. That extra oxygen flow is silicone hydrogel's clearest advantage. But it doesn't mean everyone should switch though.
| Feature | Hydrogel | Silicone Hydrogel |
|---|---|---|
| Soft contact lens material | Yes | Yes |
| Oxygen transmission | Generally lower | Generally higher |
| Main route for oxygen transport | Water in the lens | Primarily silicone component |
| High water content is required for higher oxygen permeability | More important | Less important |
| Available as daily disposables | Yes | Yes |
| Available as reusable lenses | Yes | Yes |
| Automatically more comfortable? | No | No |
| Automatically better for dry eyes? | No | No |
| Requires appropriate fitting | Yes | Yes |
What are hydrogel contact lenses?
Hydrogel contact lenses are the traditional soft lenses made from water-attracting polymers. The key thing to know is that oxygen travels through the water held inside the lens. That's why, in conventional hydrogel materials, there's a link between water content and how much oxygen the lens lets through: generally, the more water a lens holds, the more oxygen it can potentially carry. Hydrogel lenses are still widely used today and can offer excellent vision and comfort when they're the right fit for the wearer. A familiar example is 1-Day Acuvue Moist. LensesOnline currently lists 1-Day Acuvue Moist as made from Etafilcon A, a hydrogel material, with 58% water content on the 90-pack listing. The 30-pack product page lists an oxygen transmissibility of 25.5 Dk/t at -3.00D.
What are silicone hydrogel contact lenses?
Silicone hydrogel lenses are also soft lenses, but with silicone woven into the material. Silicone is naturally very good at letting oxygen through, which means silicone hydrogel lenses can transmit far more oxygen than conventional hydrogel — without needing a high water content to do it. Silicone hydrogel technology was developed largely to solve the oxygen limitations of older hydrogel lenses. Today, you'll find silicone hydrogel materials across many daily, fortnightly, and monthly lens ranges, including:
- Dailies Total1 — Delefilcon A silicone hydrogel
- Precision1 — Verofilcon A silicone hydrogel
- Acuvue Oasys — Senofilcon A silicone hydrogel
- Biofinity — Comfilcon A silicone hydrogel
LensesOnline currently identifies each of these materials on the relevant product pages.
Why does oxygen transmission matter?
Unlike most tissues in your body, your cornea doesn't have blood vessels feeding it oxygen directly. When your eyes are open, most of the oxygen your cornea needs comes straight from the air around you. A contact lens sits between the air and your cornea, so it needs to let enough oxygen through to keep your eye healthy. One of silicone hydrogel's biggest breakthroughs was significantly boosting oxygen flow compared with older hydrogel lenses. Higher-oxygen silicone hydrogel lenses have meaningfully cut down many of the eye issues traditionally linked to low-oxygen contact lens wear. That's a genuine advantage of the technology. That said, oxygen flow is only one piece of the puzzle when it comes to how a lens performs.
What does Dk/t mean on contact lenses?
You may spot the term Dk/t when comparing lens specs. It sounds technical, but the idea is simple. Dk is a measure of how permeable the lens material is to oxygen. t is the thickness of the lens. Dk/t tells you how much oxygen actually gets through a lens of that thickness. Generally speaking, a higher Dk/t means more oxygen can pass through the lens. Just be careful comparing Dk/t numbers between products, though — lens thickness can change depending on your prescription and the lens design. For most people, Dk/t is best thought of as one helpful data point, not the single number that should decide which lens you buy.
Does higher water content mean a better lens?
This is one of the most common misconceptions about soft contact lenses. A higher water percentage doesn't automatically mean more oxygen reaches your eye. That might come as a surprise. Within conventional hydrogel materials, higher water content usually does mean higher oxygen permeability, because oxygen moves through the water in the lens. Silicone hydrogel works differently. Most of its oxygen transport happens through the silicone, not the water. Because of this, some silicone hydrogel lenses actually have lower water content while still delivering far more oxygen. Here's a real-world example from LensesOnline: 1-Day Acuvue Moist is a hydrogel lens with 58% water content, currently listed at 25.5 Dk/t at -3.00D. Dailies Total1, on the other hand, has a silicone hydrogel core. LensesOnline currently lists it at just 33% core water content — yet with a Dk/t of 156. So simply comparing the water percentages on two boxes won't tell you which lens actually lets in more oxygen.
Are silicone hydrogel lenses more comfortable?
Not automatically. Since silicone hydrogel delivers more oxygen, it's easy to assume it must feel more comfortable too. But the best available evidence doesn't back up that assumption. A Cochrane systematic review comparing hydrogel and silicone hydrogel soft lenses found the evidence was of very low certainty — not enough to say one material beats the other on comfort or overall safety. A later published summary came to the same conclusion. That makes sense, because lens comfort is shaped by many things, including:
- The lens surface
- Lens design
- How well the lens fits
- How often you replace it
- Deposits that build up on reusable lenses
- The lens care system you use
- Your tear film
- Your individual eyes
A 2025 review looking back on 25 years of silicone hydrogel technology similarly points out that comfort can hinge on factors like surface friction, lens design and care routines — not oxygen flow alone. So a well-fitting hydrogel lens might feel better to you than a particular silicone hydrogel lens, while the opposite could be true for someone else.
Are silicone hydrogel lenses better for dry eyes?
Again, there's no one-size-fits-all answer. More oxygen doesn't automatically mean better dry-eye comfort. Dryness during contact lens wear can come down to your tear film, the lens surface, how well the lens fits, your environment, your replacement schedule, and the unique characteristics of your eyes. That means the right lens for someone dealing with dryness involves a lot more than just spotting the words "silicone hydrogel" on the box. Some modern silicone hydrogel lenses also include surface technologies aimed at improving moisture and wettability, but these vary from product to product. If your current lenses start feeling uncomfortable, dry or hard to wear, it's worth chatting with your optometrist rather than switching materials based on an online comparison alone. You can also check out our guide to contact lenses for dry eyes for more on the different factors worth thinking about.
Hydrogel or silicone hydrogel: which should you choose?
There's no single "right" material for every wearer.
A hydrogel lens could still be a great fit if:
- Your current hydrogel lenses fit well
- You're happy with your vision and comfort
- You prefer a particular daily disposable hydrogel lens
- Your optometrist has recommended it for you
There's no reason to assume a well-fitted hydrogel lens is outdated just because silicone hydrogel is newer technology.
Silicone hydrogel might be worth considering if:
- Higher oxygen flow is a priority for you
- Your optometrist recommends a higher-oxygen lens
- The lens design that suits your prescription happens to be silicone hydrogel
- You'd like to explore the many modern daily, fortnightly or monthly silicone hydrogel options
The key is choosing the right lens for you — not just the material. Two lenses with the same prescription power can still differ in material, diameter, base curve, surface and design. They shouldn't be treated as automatically interchangeable.
Examples of hydrogel and silicone hydrogel contact lenses
To see how these materials show up in real products, here are some examples currently listed by LensesOnline.
Hydrogel contact lens example
Silicone hydrogel contact lens examples
These examples are here to show how different materials and designs show up in real lenses — not to crown one as universally "better."
Can you sleep in silicone hydrogel contact lenses?
Don't assume a silicone hydrogel lens is safe to sleep in just because it lets more oxygen through. Daily-wear lenses are meant to come out before bed. Some specific lenses do have an approved extended-wear schedule, but that depends on the individual product and your eye-care professional's advice — not simply whether it's made from silicone hydrogel. Sleeping in contact lenses raises your risk of eye infection. The Centers for Disease Control and Prevention (CDC) recommends avoiding sleeping in lenses unless your eye-care provider has specifically told you it's okay. If you're ever unsure whether your lenses are safe for overnight wear, check the manufacturer's instructions and check in with your optometrist.
Five common myths about contact lens materials
1. "The higher the water content, the more breathable the lens."
Not necessarily. That link holds true within conventional hydrogel materials, but silicone hydrogel carries most of its oxygen through silicone, not water.
2. "Silicone hydrogel is always more comfortable."
There isn't enough high-quality evidence to say this.
3. "Silicone hydrogel is automatically better for dry eyes."
Not necessarily. Dry-eye comfort depends on far more than oxygen flow.
4. "All silicone hydrogel lenses can be slept in."
No. Wearing schedules are product-specific, and sleeping in lenses can raise your infection risk.
5. "If two lenses have the same prescription, I can swap between them freely."
Not automatically. Lenses can differ in fit, material, diameter, base curve and design, even with the same prescription power.
So, is silicone hydrogel better than hydrogel?
Silicone hydrogel clearly wins on oxygen transmissibility. That's one of the most important advances in modern soft lens materials. What the evidence doesn't show is that silicone hydrogel is automatically more comfortable, safer, or better suited to everyone. Current research simply isn't strong enough to crown one material over the other purely on comfort and overall safety. For some people, silicone hydrogel will be the best fit. For others, a well-fitting hydrogel lens will keep delivering great vision and comfort. Rather than choosing based on a single spec — material, water percentage or Dk/t — it's worth looking at the whole picture: fit, surface technology, replacement schedule, prescription parameters, and how the lens actually performs on your eyes. If your current lenses are comfortable and working well, there's no need to switch just because another material sounds more advanced. But if you're noticing dryness, redness, discomfort or shorter wearing times, it's worth talking to your optometrist about whether a different lens material or design could suit you better.
Frequently asked questions
What's the main difference between hydrogel and silicone hydrogel contacts?
The main difference is how each material carries oxygen. Conventional hydrogel relies mostly on the water in the lens, while silicone hydrogel uses silicone to achieve much higher oxygen permeability.
Which has more oxygen: hydrogel or silicone hydrogel?
Silicone hydrogel lenses generally offer significantly higher oxygen transmissibility than conventional hydrogel lenses.
Is silicone hydrogel more comfortable?
Not necessarily. Current systematic-review evidence doesn't show a clear comfort advantage for silicone hydrogel over hydrogel.
Is a higher water-content lens better?
Not automatically. Water content affects hydrogel and silicone hydrogel materials in different ways, so it shouldn't be used on its own to judge oxygen flow or overall lens performance.
Are silicone hydrogel lenses good for long days?
Their higher oxygen transmissibility can be a real advantage, but how long you should wear any particular lens depends on the lens itself, your eyes, and your eye-care professional's advice.
Can I switch from hydrogel to silicone hydrogel using the same prescription?
Don't assume lenses are interchangeable just because the prescription power matches. Different brands can have different materials, designs, base curves and diameters. Talk to your optometrist before switching lenses.
Can I sleep in silicone hydrogel lenses?
Only if your specific lens has an approved wearing schedule and your optometrist has advised you accordingly. Being silicone hydrogel doesn't automatically make a lens suitable for overnight wear.
References:
https://pubmed.ncbi.nlm.nih.gov/37724689/ https://pubmed.ncbi.nlm.nih.gov/39016303/ https://www.cdc.gov/contact-lenses/about/about-contact-lens-types.html