SQUARE CLIP-ONS
Choose the square style that most closely resembles that of your prescription glasses.
Use a millimeter (mm) ruler to measure across the front of one of your prescription lenses (see example diagram to the right)—this will be your size for your clip-ons. Make sure that the clip-on size you select is at least as large as your lens measurement.
If your lens measurement is not listed in the size options, select the next largest size clip-ons. For example: if your lens measures 55mm, your best option would be a size 56.
PRINTABLE SIZING GUIDES
Alternatively, you can browse our comprehensive clip-ons sizing guides. First, identify the shape (Oval, Round, Rectangle, or Square) that most resembles the shape of your prescription eyewear frame. Next, place your glasses face down on the full scale images of each size within the shape collection to find the size that is most accurate to the shape of your glasses.
