When choosing the size of Ray-Ban sunglasses, you have to consider the various width measurements given in the sunglasses' specification details. This can be accomplished by approximating the width of the sunglasses with a ruler relative to your facial features. However, the best way to choose the right size of Ray-Ban sunglasses is to visit a licensed retailer and try on multiple sizes in person.
Look at the sizing information of the Ray-Ban sunglasses you are considering. The "eye" size is the width of the sunglasses lens. This is determined by measuring the diameter of the lens on the inside of the frame at its widest point. The "bridge" size is the measurement between the two lenses at its smallest point. These measurements are given in millimeters.
Study the general shape of your facial features, and consider this when choosing a sunglasses size. If the bridge of your nose is wide, choose sunglasses with a wide bridge measurement to allow the sunglasses to sit further down on your nose. To accentuate the upper part of your face, choose narrower lenses that won't stick out beyond the widest part of your face. In contrast, larger lenses that stick out beyond your face provide balance to wide cheekbones.
Pinch the bridge of your nose with your fingers, at the point where you want the sunglasses to rest. Remove your fingers while keeping them spread at the width of your nose bridge. Measure this width with a ruler to determine the approximate width of your nose bridge. Compare this measurement to the bridge sizes of the Ray-Ban sunglasses options you are choosing from. Choose the closest size that is wider than your nose bridge for a comfortable fit.
Hold the ruler up to your eye while looking in the mirror. Spread your fingers so that they are spaced apart at the same width as the lens of the sunglasses you are considering. Use the space between your fingers to determine the approximate size that the Ray-Ban lenses will be. This allows you to picture how far the lenses will stick out, as well as the general shape of the lenses relative to your face.
Go to a Ray-Ban authorized sunglasses retailer if you are still having trouble choosing a size. There you can try on multiple sizes of sunglasses and decide which is best based on comfort and appearance. This is the only way you can be certain in choosing the proper size.