Single-vision lenses offer one correction throughout the entire lens (typically for distance or reading) while progressive lenses offer multiple corrections in one lens, providing transition from distance correction on top to reading correction on bottom. This means you can do not need multiple pairs of glasses for different situations.

OS (oculus sinister) means the left eye and OD (oculus dextrus) means the right eye. The further away from zero the number on your prescription, the worse your eyesight and the more vision correction (stronger prescription) you need.  A “plus” (+)  sign means you are farsighted, while a “minus” (-) sign means you are nearsighted.

If there are three numbers in your prescription, you have astigmatism. These numbers are written as S x C x Axis. The S is "spherical", which refers to nearsightedness or farsightedness discussed previously. The C refers to the "cylinder" or astigmatism, and can be a negative or a positive number. The bigger this number, the more astigmatism you have. The Axis is a number anywhere between 0 and 180 degrees. It reveals the orientation of the astigmatism. It is not enough to specify how much astigmatism there is; we have to know where the difference in curvature is taking place in order to successfully fulfill your prescription.

No, contact lens prescriptions are different than glasses prescriptions, so you cannot use a contact lens prescription to order glasses.

Yes, your RX for sunglasses will be the same as your RX for your glasses.

Pupillary Distance, the distance in millimeters between your pupils.

Go to your local optometrist and receive a prescription, including your PD, or pupillary distance, from them.

Yes, but you will need to determine if you would like the prescription to be filled for distance vision or near vision (readers).

Lens power is affected by how close a lens sits to the eye. This is called Vertex Distance. A minus lens moved closer to the eye gets stronger while a plus lens moved closer to the eye gets weaker. By default throughout the optical industry 10mm is the accepted vertex distance which coincides with how far doctors will normally conduct a patient refraction. This distance definitely varies from person to person due to the way our noses are wider, longer, sitter higher up, etc. from one another but this distance should be around 10mm.

All of the frames in our Austin Collection have three nosepad sizes for you to find the optimal fit for your nose bridge width.

That's why we have our Home Try On feature! Try on the styles you select in the comfort of your own home!

Unfortunately, no. A child's pupillary distance is too narrow for our current selection of frames.

The GEKO™ padding on the nose and temples make our glasses stay on your face in all conditions. All of our frames are remarkably lightweight, very durable, and have premium lenses with the most advanced combination of lens coatings on the market. On many of our optical frames, we offer multiple nosepad sizes as well as bendable titanium temples to completely lock down your fit. We don't skimp on quality materials to save dollars.

The numbers on the inside of the temple represent the size of the eyewear. The first number is the width of the lens. The second number is the distance between lenses. The last number is the temple length. All measurements are in millimeters (mm).

Below are the prescription ranges for our lenses and frames.

1. Choose up to 4 frames to try on.
2. We ship you demos of your picks.
3. Try them for up to 7 days.
4. Order your new glasses at any time. Any fees go towards purchase price.
5. Return all of your demos with free shipping

We use a demo fleet because the vast majority of eyeglasses purchased will be with prescription included, which we cannot fill for a home try-on order. Once you find the perfect pair among the demos you selected, you can order that pair with prescription at roka.com.

You can try your demo frames at home for up to seven days.

Simply re-pack the frames in the box you received it in, affix the prepaid returns label on the outside of the white box and drop it off at your local UPS store.