What's my prescription?

If you have had an eye test in the last two years, then you can refer to your previous prescription. If you think your vision has changed, or you haven't had a recent eye test, it is always best to book an eye examination with an optician to find out your current prescription.

Reading your prescription

To calculate the power, you need to take into account the two aspects of your prescription.

The cylinder (CYL) indicates the amount of lens power for astigmatism. If nothing appears in this column, either you have no astigmatism, or your astigmatism is so slight that it is not necessary to correct it with your prescription lenses.

If you don't have astigmatism (no CYL figure), your prescription will be the sphere (SPH) reading. The sphere is the main part of your prescription and will be '–' for short-sightedness (myopia) and '+' for long-sightedness (hypermetropia).

OD = Right eye
OS = Left eye

If you don't have astigmatism and your sphere falls between two of the options on offer (ends with a .25 or .75) always move down to the next available lens. For example, if your prescription is -3.75, then move down to -3.5. HUUB prescription lenses are available in .5 increments.

If you have astigmatism

At HUUB, we use a method called sphere equivalency to determine what lens to use when there is some astigmatism. If your astigmatism is over 2.00 (as indicated by the CYL value), you may need to consider a custom product for the best results.

Use the formula below to work out the required dioptre required for each eye.

OD = Right eye
OS = Left eye

Dioptre = SPH + (CYL / 2)

Please note for goggles you don't need to take into account the Axis.

Example prescription:

OD (right eye) – SPH -3.0, CYL -2.0
OS (left eye) – SPH -2.5, CYL -1.0

Lenses needed:

Right eye = -3.0 + (-2.0 / 2) = -4.0
Left eye = -2.5 + (-1.0 / 2) = -3.0

If your dioptre falls between two of the options on offer, always move down to the next available dioptre. For example, if your prescription is -3.75, then move down to -3.5. HUUB prescription lenses are available in .5 increments.

What is the highest prescription lens available?

In our prescription lenses, the highest we can do is -6.00 through to -1.50 in increments of 0.5, both for short-sighted corrections.

How do I fit my prescription lenses?

You will need to purchase the Altair Swim Goggle, plus Altair Prescription Lenses. It is really easy to change the lenses. If you are not sure how to do this, watch our 'How to change Altair lenses' video.