prescription swim goggles

Need Help Choosing Prescription Swim Goggles?


Prescription Swimming Goggles Help

What do I need to do first?

Before Choosing Prescription Swimming Goggles, find out what your existing eyeglass prescription is! The person who tested your eyes or who dispensed your last pair of glasses will have this information and will give you the details. The prescription numbers will contain some uncommon terms, such as:

  • OD – Ocular Dexter (simply means your RIGHT eye)
  • OS – Ocular Sinister (your LEFT eye)
  • Sphere – This measures the degree of weakness in diopters and for nearsighted (myopic) people this is always a (-) negative number
  • Cylinder – This refers to the degree of astigmatism in the eye. In selecting step diopter lenses (which do not correct for cylinder) you must add one half (½) of this number (to a maximum of .50 diopter) to the sphere number to determine the correct step diopter lens!

CAUTION: Ophthalmologists often use a + (positive) number for cylinder and you then have to be careful with the + and – signs when doing the calculations!

How do I choose the proper strength lens?

Choosing the proper strength lens can seem a little confusing, which is why we have provided you with a quick and easy way to determine what lens strength is right for you.

The selection of appropriate corrective lenses for the swimming goggles does require some understanding of your visual acuity requirements and your most recent prescription.


How do I calculate my lens strength?

Choosing Prescription Swimming Goggles lens strength can be done easily by using our calculator or manually by using the formula below.

Enter the Sphere and Cylinder values from your prescription to determine which diopter strength would best suit you. Be sure to select + or - for each and enter all four values.
*This measurement is only a suggestion. It is best to confirm your diopter strength with your optometrist.
Sphere Cylinder Diopter Strength
O.D. (right eye)  
O.S. (left eye)  

SPH____ + 1/2 Cyl ____ = _____

For example,

  • If the sphere (Sph) is -2.5 and the cylinder (Cyl) is -1, then -2.5 + (1/2 x -1) = -3 step diopter lens: Adding -2.5 and -0.5 together
  • If the sphere is -4.0 and the cylinder is +1, then -4.0 + (1/2 x +1] = -3.5 step diopter lens: Adding -4 and +0.5 together

*Note that we do not recommend moving more than 0.50 in either direction,.

In situations where the cylinder is 0, the same formula is still used.

For example,

  • If the sphere is -2.5 and the cylinder is 0, then -2.5 + (1/2 x 0) = -2.5 step diopter lens
  • If the sphere is -4.0 and the cylinder is 0, then -4.0 + (1/2 x 0) = -4 step diopter lens

See, simple! By plugging in the appropriate values into the formula above, you can determine what lens strength you need for your Aquagoggles prescription swim goggles!

Do not move more than a 0.50 diopter step in either direction from your sphere.

Once you have this information, our goggles can be selected here.

If you have any questions, don’t hesitate to contact us

There is also a great tool at Glasses Simulator


Special Considerations

In order to produce lenses for swimming goggles, and keep the price reasonable they are made in one-half (.5) diopter increments. These lenses are not a full custom prescription and do not correct for cylinder or astigmatism. They are not intended for full-time wear. Extended wear of step diopter lenses will cause various degrees of eye strain but they are more than adequate for occasional wear especially if the cylinder is close to or less than 1.

Always move DOWN to the closest step diopter! If the calculation of your prescription shows that you should have a -2.75 (step diopter lens) then you should choose a -2.5 lens for the swimming goggles. This causes less strain and you will be unlikely to notice any significant loss of acuity within a reasonable distance. There is also a slight magnifying effect when underwater.


Getting used to Step Diopter Lenses

The corrective lenses in these swimming goggles do not have correction for cylinder and are not a direct match for your regular prescription but are more than adequate for temporary use.

A number of swimmers have told us that it takes a short while to adjust to their goggles. Wear them for a few minutes, your eyes will adjust and you will be more than satisfied with the results! Enjoy your swimming experiences and please drop us an email with your comments.


Fitting and Care Instructions

We appreciate your business and trust you have received your order in perfect condition. If there is a problem with your order, please contact us so that we may correct this issue as soon as possible.

Please note that the goggle lenses are of step diopter construction. This means that they will not exactly match your prescription and are not meant for prolonged use. Aquagoggles are recommended for recreational swimming and should not be used for diving or other high-impact water sports. Careless or inappropriate use can cause injury.


Fitting your goggles

Goggles come pre-assembled with the seal/strap combo already in place. All you have to do is adjust the head strap tension to suit your size and comfort. Remember, tighter is not necessarily better, as this may cause discomfort and markings around the eyes.

Goggles are also shipped with Small, Medium and Large sized nosepieces. The Medium nosepiece comes pre-installed. If the goggles do not fit right, stand in front of a mirror with the goggles held to your eyes and without the nose bridge installed. Find the most comfortable position. Select the nosepiece that best fits your comfort position (the space between the lenses) and clip the nosepiece in place.


Removing the nosepiece

Firmly grip the outside of an eyecup piece and the nosepiece. Carefully pull on the nosepiece until it pops out. A small twist and pull motion may be needed as the nosepiece fits quite snuggly.  For a demonstration, Aquagoggles Youtube!


Removing and replacing seal/strap

Removing the seal/strap is easy since the Silicone stretches. Carefully pull the seal, starting with the widest end, away from the lens. Pay close attention to how the seal is removed since you’ll be replacing it in the same position. It’s much easier to remove and install with the nosepiece removed. To install, start with the narrow end of the lens and insert it into the narrow end of the seal. There will be a slit in the middle of the seal for the lens to fit in. Push the lens as far down into the seal as possible (try to get it as close to centered as possible as well), then pull the seal forwards and push the other end into the top of the lens cup groove, then work the seal around the lens into the molded retaining groove. A rolling and pushing action with your thumb will help ensure a full seal. You will faintly see the seal in the groove of the lens. This will ensure that the seal is on the lens properly.

Click here to watch a demonstration on Youtube.

Adjusting strap

When adjusting the straps for correct tension, DO NOT PULL on the ends of the straps BEFORE you have slid the end sideways out of the ladder retaining clip. This end half loop has an edge that can “nick” the silicone strap and then results in tearing. Note: Do not over tighten, silicone seals do not require much compression to seal properly.


Eyecup Seal

The eyecup seals are part of the strap assembly and fit tightly around the lens itself. If you do peel off this seal for any reason it can be replaced but you do have to stretch & push/roll the seal inwards to get a proper seal. This will take some time to accomplish!



These lenses have been coated with an anti-fog solution during manufacture. This coating will scratch easily and soap or other surfactants can damage the coating. Rinse and shake to dry ONLY. Using fingers, tissues or cloth will scratch the anti-fog coating inside the lenses.


Removal of Anti-fog coating

If you have scratched the coating inside the lens or damaged it by using detergents or other surfactants there is a solution! You can use isopropyl alcohol (rubbing alcohol) to remove all of the factory applied coating. Pour some alcohol inside the lens & let sit for a few minutes then use a fingertip to rub around the inside of the lens, removing the coating and then rinse under hot water. It is not necessary to remove the silicone seals or strap as alcohol will not affect the silicone. Now you have an untreated polycarbonate lens!

If you want an aftermarket solution, we carry Zero-Fog. But there are other options.  Your local optometrist or sporting goods store should carry some.

Additional instructions are included with your goggles (blue insert).


Guarantee, Privacy, and Ordering takes your business seriously and we take all steps necessary to ensure that you can order from us confidently. Please read the following section to learn more:


If you need additional help Choosing Prescription Swim Goggles, please contact us directly and we’ll do our best to answer your questions.



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23 thoughts on “Need Help Choosing Prescription Swim Goggles?

  1. My eye doctor told me to add the Axis which I have in my prescription but I don’t see that option…
    Here is what I have for far sightedness.

    Right -3.25 (sphere), -1.0 (Cylinder), 100( Axis)

    Left -3.75 (sphere), -.75 (cylinder) 85 axis

    1. Mark,

      The lenses correct for Sphere only, but we can adjust based on the Cylinder (Astigmatism) as a workaround.

      For you, if we took the whole 1/2 of your Cyl it would end up being -3.75 Right, and -4.125 Left. So we step down a bit from those numbers and get -3.5 Right, and -4 Left.

  2. If my son’s prescription is: OD: -400 -150 *180; OS: -300 -175 *168
    What would be his prescription for swim goggles?
    Thank you.

    1. Helen,

      I’d recommend -4.5 Right and -3.5 Left for your son. Won’t be perfect, but should still work quite well for him.

  3. Hello, the online ordering asks for a diopter for each eye. I have my prescription and can not find the diopter number. I do have an “Axis” number of 150 and “Add” OD number of +2.25 and OS of +2.25.
    Can you help so I can complete my order?

    Thank you.

    1. David,

      They wouldn’t be perfect, but the V2+ in +2 strength would work best for you.

  4. Ordering goggles for an 11 year old girl with a small face. Prescription is -2.25 right eye and -1.75 left.
    Please suggest what to order?

    1. Jessica,

      I’d suggest stepping down slightly. So -2 for her Right eye, and -1.5 for the Left. Should work very well with the small nosebridge.

  5. OD: sphere +2.35, cylinder -0.75, (Axis 100) Diopter Strength: +1.875
    OS: sphere +1.25, cylinder -0.75, (Axis 058) Diopter Strength: +0.875
    It appears I might benefit with +2.0 on right eye, but not on left. Is it possible to get one regular lens in a pair? Or would the +2.0 be ok for both eyes?

    1. Pat,

      Yes it would work out to +2 and +1 for you (Roughly). Unfortunately our lenses start at +2, and we do not have a 0 in that style.

      If you’d like to see what +2 would be like for your Left eye (OS) then I’d suggest trying on a pair of the +2 reading glasses at your local pharmacy (Walgreens etc). They would be doing pretty much the same thing as our prescription swim goggle lenses.

      1. Graham, Thank you for your quick response!

        I wear bifocals most of the day with the ADD prescription of +2.50 for reading, cooking, computer use etc . I also have +2 readers stashed around in different places for quick use. +2 would be a bit strong for any distance more than a computer screen away for me. I could use some distance correction for underwater lifeguard rescues but +2 would not be helpful with that.
        Thanks for you help, Pat

  6. I am looking for a pair of goggles for swimming laps at the local Y and for snorkeling when I go on cruises. My prescription is as follows
    SPH +2.5 CYL-0.50
    SPH +3.50
    What would you recommend.

    Cheryl Wells

    1. Cheryl,

      While they wouldn’t be perfect, the V2+ (Blue ones) in +3’s should help immensely.

  7. Right eye:
    sphere (-7.25) cylinder (-2.50) axis (+010)
    Left eye:
    sphere (-6.25) cylinder (-2.75) axis (+180)

    What would you recommend? I am planning to learn swimming recently and wants to see clearly.

    1. Nicole,

      I would say that a -8 Right, -7 Left should work pretty well for you. Not perfect due to your astigmatism, but much better than nothing.

      1. Here is what my daughter has, what should she wear?

        Right -4.50 (sphere), -1.0 (Cylinder)

        Left -5.50 (sphere), -1.0(cylinder)

        Thank you

        1. Nurul,

          She would use a -5 Right, and -6 Left. Should work quite well for her.

  8. OD = -1.25
    OS = -1.125

    Should I consider the -1.5?

    I do triathlons and sporting distances is important

    1. Ben,

      They’d be just a little stronger than you need, so should be fine for the period you’re in the water (1-2 hours? Ironman?)

      That’s where I started myself actually, when my eyes were a little better than they are now.

  9. My doctor didn’t mentioned the cylinder he mentioned only the sphere (Right eye – 2.5 and Left eye – 1.75), what is the myopia number should I get in my goggles?

    1. That’s a good thing! In your case, -2.5 Right, and step down the quarter diopter and use -1.5 for the Left. That should work really well for you.

  10. Hello, I have an OD -5.375 &
    O.S. -5.625. I think I need a 5 & 5.5. Is this close enough to just get 1 pair in size 5 or do you recommend getting 2 pair & swapping lenses?

    1. Darren,

      You could go with -5.5 for both eyes, or step down with your right and select -5. No need to swap lenses, we let you choose a different lens for each eye!

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