How to snorkel with glasses

If you wear glasses and you are about to go snorkeling, you have probably already spotted the problem. The glasses are not coming with you, and without them the reef is a green blur.

This is a thoroughly solved problem with four real answers at wildly different prices, and one of them is free. The work is in picking the right one for your eyes rather than the first one you find.

Why glasses under a mask don’t work

Two separate things go wrong, and people usually only anticipate the first.

The earpieces break the seal. A mask seals against a continuous ring of skin around your face, and the arms of your glasses cross that ring on both sides, holding the silicone off your skin. Water comes in. Not dramatically, just steadily, for the whole swim, and you spend the trip clearing your mask instead of looking at fish.

The lenses also end up in the wrong place. Spectacle lenses are ground to sit about 12mm in front of your cornea. Pressed flat against a mask lens, or held away from your face by the shape of the skirt, they no longer sit at that distance, and the correction stops matching your eyes. You get a leaking mask and worse vision than you started with.

That is also the honest answer to a question a lot of people search for. There is no snorkel mask that fits over glasses. Full-face masks look roomy enough from outside and are not: the internal shape exists to seal around your nose and mouth, and a frame has nowhere to go. Both objects want the same piece of your face and only one of them can have it.

“Snorkeling glasses” are not really a product

People search for snorkeling glasses, and it is a reasonable phrase that hides a real distinction.

Goggles seal around the eyes and leave the nose out. Prescription swimming goggles are cheap and they work well for lengths in a pool. For snorkeling they are a poor choice, and the reason only becomes obvious once you are in the water. With your nose outside the airspace you cannot equalize if you drop below the surface. You cannot clear them by blowing water out through your nose either.

A mask covers the eyes and the nose. That single design difference is why every serious answer here involves a mask. You can pinch your nose and equalize, and you can clear a flooded mask by exhaling into it.

So snorkeling glasses as a distinct product barely exist. What exists is a mask with corrective lenses in it, which is the third option below.

Start here: which of these are you?

Four situations, four different answers. Find yours and you can skip most of this page.

• Mild prescription, inside about ±1.00. Try nothing at all first. The water may do the job for free. Test it in a pool before you spend anything.
• Moderate prescription, no real astigmatism, one holiday a year. Soft daily disposable contacts. Cheapest by a distance, and what most people in your position settle on.
• Moderate to strong prescription, or you snorkel several times a year. Corrective lenses in the mask. Our guide to prescription snorkel masks covers what each mask actually ships and what the lenses add.
• Astigmatism, very uneven eyes, or over 40 and wanting to read a camera screen. These are the cases where the off-the-shelf answers quietly fail. Read prescription snorkel masks and astigmatism before buying anything.

Before you spend anything, check it is not fog

This sounds too obvious for a heading. It is also the most common false alarm we hear about, and it costs nothing to rule out.

A new mask arrives with a film of silicone left over from manufacturing on the inside of the lens, and that film will fog the mask no matter how good your vision is. People come out of a first foggy swim convinced they need corrective lenses when what they actually needed was to scrub the film off and treat the lens with a defogging agent. Our guide to cleaning and preparing snorkeling gear has the method.

The two problems feel different once you know what to compare. Fog is milky and uniform, it gets worse the longer you are in the water, and it clears for a few seconds if you let a little water in and swill it around the glass. Uncorrected vision is soft everywhere, stays exactly as soft for the whole swim, and does not respond to swilling water at all.

What the water does for you for free

A mask puts a pocket of air in front of your eyes, and light bends as it crosses out of the water into that air. Everything looks bigger and closer than it is.

The figure usually quoted is 33 percent larger and 25 percent closer. That 33 percent is a theoretical ceiling. Real magnification depends on how far the object is and how far your eye sits behind the faceplate, and in ordinary snorkeling conditions it lands nearer 25 or 28 percent¹². Either way, the whole reef arrives a quarter to a third larger than life at no cost to you.

For a mild prescription, roughly inside +1.00 to −1.00, that is often enough for a genuinely good time. You will not read the small print on a dive watch. You will see fish, coral heads, texture and color.

Testing it is easy and I would do this before spending a penny. Borrow or hire a mask, get in a pool, look at the grout between the tiles on the bottom and then at somebody at the far end. If the detail satisfies you, you are finished, and you have saved yourself a few hundred dollars.

For me it was not quite enough. Better than nothing, and pleasant enough. What I could not shake was a sense that I was looking at approximations of fish and coral. Once you notice that, it is hard to stop noticing.

The four options

Rely on the magnification

Free, nothing to carry, nothing to order, nothing to lose in the water. It works inside about ±1.00, does nothing for close work like a camera screen or a gauge, and does nothing at all for astigmatism. Ten minutes in a pool tells you whether you are done.

Contact lenses

The default answer for most people, and the cheapest thing that handles a real prescription.

Two things matter more than the rest. Wear soft daily disposables, so a lens that has been in the water can simply go in the bin, which is what the FDA advises for any lens that has been submerged³. And when the mask floods, keep your eyes shut until you have surfaced and cleared it. Opening and blinking is how lenses get lost.

I still use contacts, mostly when the swim is incidental. A boat trip with one snorkeling stop, or a hotel beach where I would rather not carry a mask through an airport. The infection question, the lens types and what to pack are all in can you snorkel with contacts.

Corrective lenses in the mask

This splits into two quite different products.

Drop-in lenses, sometimes called pop-in lenses, clip into a mask built to accept them in place of the clear lens. They are spherical only and come in 0.5 diopter steps, typically covering about −1.0 to −8.0 for nearsightedness and +1.0 to around +4.5 for farsightedness⁴⁵. Cheap, and swappable when your eyes change.

Bonded lenses are ground to your prescription and fixed to a mask by a lab. This route corrects anything, including astigmatism, prism and a bifocal reading segment. It is permanent, and it is the expensive one: single vision runs around $289 to $359 a pair and bifocals $359 to $399, before the mask⁶.

Which masks take which kind of lens is the subject of our prescription snorkel mask guide. One thing to know before you shop: almost every mask sold as a prescription snorkel mask arrives with clear lenses, and the correction is a second purchase.

Stick-on magnifiers

A flexible lens that sticks to the inside of your mask and creates a near-vision zone low in your field of view. Cheap, removable without damage, and specifically aimed at close work: camera screens, gauges, small creatures on the rock.

If your distance vision is fine and a camera screen has become unreadable, this is very likely the cheapest thing that will fix your actual complaint. It also sits in your field of view whether you want it there or not, and it is fiddly to position well the first time.

Choosing between them

	Contacts	Drop-in mask lenses	Custom bonded lenses
Roughly what it costs	A few dollars a trip	$100 to $160 all in	$350 to $550 all in
Prescription strength	Almost any	About −8.0 to +4.5	Any
Astigmatism	Yes, as prescribed	No	Yes
When your prescription changes	Order the new one	Replace one lens	Replace the lenses
Bifocal and close work	As prescribed	Twin-lens masks only	Yes, positioned to order
Works out of the water	Yes	No	No
Lead time	None	None	Two to four weeks

For one holiday a year, contacts win. A week of dailies costs a few dollars against $100 for the cheapest complete mask setup, and it takes many years of annual holidays before the mask catches up. Anyone telling you otherwise on a page that earns a commission on masks is worth reading sceptically, this one included.

Three things change that arithmetic. Snorkeling several times a year collapses the cost per swim. Contacts that do not suit your eyes remove the cheap option altogether. And real astigmatism changes the comparison completely, because drop-in lenses cannot help you, so the choice becomes contacts against custom lenses at $350 or more.

A fourth reason decided it for me, softer than those three. At some point you want to stop thinking about your eyes in the water.

What I use, and what I tried first

I use a prescription mask now, and I got there by working through the alternatives rather than by choosing well at the start.

Going without correction was pleasant and insufficient, as above. Contacts worked, and I still use them for the right kind of trip. What pushed me to look further was not an incident. Nothing went wrong. It was a low-level awareness that a flooded mask was a small problem to be managed. Over enough boat trips, that turned out to be more tiring than it sounds.

The mask took that away entirely, which is the honest reason I prefer it. The vision is comparable. What changed is that nothing is at stake.

The mistake I would warn anyone off is the one I made, which is researching this backwards. I spent a long time comparing lens specifications and almost none of it checking whether a given mask actually fitted my face. A well-sealed mask with slightly rounded-off correction beats a leaky mask with a perfect prescription every single time, because you will spend the swim clearing the leaky one. Get the fit right, then put lenses in it.

And I would not push anyone with a once-a-year holiday toward a mask, whatever I happen to prefer for myself. The arithmetic does not support it.

A note on what we removed

This page used to carry instructions for gluing lenses out of an old pair of glasses into a mask with waterproof adhesive. We have taken them out and we are not putting them back. Setting rigid frames and hand-glued glass a centimeter from your eyes is not something we will put our name to. It saves perhaps $50 against a pair of drop-in lenses, which nowhere near justifies it.

If you are already on holiday with none of this

Custom lenses take weeks and contacts need a prescription, so if you are reading this the night before a boat trip, here is the realistic order.

1. Go anyway and see how you get on. With the magnification working for you, a moderate prescription is often more usable than you would guess. Take the trip, then decide whether it is worth solving properly.
2. Ask the dive shop. Operators who run snorkeling trips field this constantly, and plenty keep a few masks with common nearsighted lenses as rentals for exactly this reason. Asking costs nothing and it is the fastest fix available.
3. Buy daily disposables locally, if you already wear contacts. Pharmacies in tourist areas often stock common powers, and your prescription is on your phone if you followed the advice in the contacts guide. Skip this if you have never worn lenses. The morning of a boat trip is the wrong time to try them for the first time.
4. A stick-on magnifier, if your problem is specifically close work. Small, cheap, and sometimes sitting in a dive shop display case.

What not to do is improvise a way to hold your glasses inside the mask. It breaks the seal it is trying to work around.

Frequently asked questions

Frequently asked questions

Can I wear my glasses under a snorkel mask?+

No. The earpieces cross the mask's sealing surface on both sides, so it leaks, and the lenses end up at the wrong distance from your eyes, so your vision degrades rather than improves. No mask fits over glasses, because the frame and the seal want the same piece of your face.

Do I need any correction at all for snorkeling?+

Possibly not. A mask magnifies everything by roughly a quarter to a third, and inside about plus or minus 1.00 that is often enough to enjoy a reef with no correction whatsoever. Testing it in a pool costs nothing.

Are contact lenses a good option for snorkeling?+

They are the cheapest thing that works for a real prescription, with genuine caveats. Use soft daily disposables, never rigid or gas-permeable lenses, and know that the FDA advises against exposing lenses to water at all. Our guide to snorkeling with contacts covers the trade-off honestly.

Should I buy a prescription snorkel mask?+

It earns its money if you snorkel several times a year, if contacts do not suit you, or if you would rather stop thinking about your eyes in the water. For one holiday a year, contacts win on cost by a wide margin.

What if my prescription keeps changing?+

Buy a mask that takes drop-in lenses rather than one with lenses bonded permanently to the frame. When your prescription moves you replace a lens for a few tens of dollars instead of the whole mask.

What if I have astigmatism?+

Off-the-shelf mask lenses do not correct astigmatism at all. At a cylinder of 0.75 or below you probably will not notice underwater. At 1.00 or more you will, and custom lenses are the only fix.

Where to go next

• Shopping for a mask: prescription snorkel masks, and what you are actually buying
• Holding a prescription with a cylinder value on it: prescription snorkel masks for astigmatism
• Leaning toward contacts: can you snorkel with contacts?
• Diving as well as snorkeling: prescription dive masks, where the mask has to be depth-rated and reading a computer becomes close work

---

References

Footnotes

1. “Do Things Seem 33% Bigger Underwater?” ScubaGeek, scubageek.com. ↩

2. “How much bigger does stuff look underwater?” Institute for Environmental Research and Education, iere.org. ↩

3. “Contact Lens Risks.” U.S. Food and Drug Administration, fda.gov. ↩

4. “Prescription Dive Masks.” Alert Diver, Divers Alert Network, dan.org. ↩

5. “Prescription Dive Mask Guide: Find Your Perfect Fit.” Mike’s Dive Store, mikesdivestore.com. ↩

6. “Prescription Dive Mask Custom Lens.” Riverside Scuba, riversidescuba.com. ↩