How does glasses sizing work?

Most glasses and sunglasses come in a range of sizes and we often have customers ask what size they are. Glasses manufacturers print multiple measurements on their frames so this often makes thing more complicated.  The size numbers you see on a glasses frame relate to the eye size (that's the measurement of the width of the lens), the length of the glasses arms, and the distance between the two lenses.

Might think that if you've found a glasses frame in a size 50 then another size 50 will fit you just as well. Unfortunately this is usually not the case. This is because that 50 measurement only relates to one specific measurement of a part of the frame and not the frame as a whole. Two glasses marked as the same size might feel and fit very differently.

So why do glasses manufacturers add size information at all? Most glasses frames are available in multiple sizes, so the size information on the frame helps us to differentiate between those different size options. So if you've found a frame you like and it feels a little big just ask us if it's available in a smaller size. Also those numbers printed on the frame can help us as opticians when we come to add your prescription lenses to the glasses frame. 

Generally we say ignore the sizing. Find somewhere to try as many glasses designs as possible and take your time choosing something that looks and feels good.

For more tips on choosing your glasses try our guide here