Look inside the temple arm of any pair of glasses and you will usually find three small numbers, something like 52-18-140. Most people never learn what they mean, but they are the most reliable way to check whether a frame will actually fit before you buy — more reliable than face shape alone.
Lens Width
The first number is lens width in millimetres — the horizontal width of a single lens. This is the main number that determines whether a frame will feel right for a narrower or wider face. Our catalogue spans a range here, from narrower rectangular styles to wider square and oversized shapes like the Mega Wayfarer and Mega Clubmaster.
Bridge Width
The second number is bridge width — the distance between the two lenses, which sits across your nose. Get this wrong and a frame either pinches at the nose or sits too low, no matter how good the lens width is. This is one of the most common reasons a frame that looks right online feels wrong the moment you put it on, and why in-person fitting matters.
Temple Length
The third number is temple length — the arm that runs from the hinge back to your ear. Too short, and the frame will feel tight behind the ears; too long, and it will sit loosely or slide down. Temple length is also the easiest of the three to adjust after purchase, which our team can do in-store.
Why This Matters More Than Sizing Charts
Generic small/medium/large sizing does not exist in eyewear the way it does in clothing — two frames labelled the same 'size' by a brand can have completely different bridge widths. The three measurements together are a far more accurate way to compare frames, especially if you already own a pair you like and want to check how a new frame compares before buying.
Getting It Right
If you are unsure how to read these numbers on a frame you're considering, bring in a pair of glasses you already own and we'll compare the measurements directly, or fit you in-store against a few options. Read more about how we approach fitting on our in-store experience page.