How to Buy Sunglasses Online Without Guessing the Fit
Buying sunglasses in a shop takes about four seconds. You put them on, you look up, and you know. Buying them online takes longer, because the one thing you actually need — whether they suit your face — is the one thing a photograph can't tell you.
The numbers can, though. Every pair we sell lists five measurements, and once you know which ones matter you can work out the fit before you order, using a pair you already own as the reference.
The five measurements
Every product page on this site carries the same five, in the same order.
Temple length is the arm — from the hinge to the tip that sits behind your ear. This one decides whether the frame stays put. Too short and it grips your temples; too long and the frame slides down your nose every time you look at your phone.
Lens height is the vertical measurement of one lens. It governs how much of your face the frame covers, and it's the main difference between a pair that reads as discreet and a pair that reads as a statement.
Lens width is one lens measured across. Along with the bridge, this is what determines whether the frame is proportioned to your face.
Frame width is the full span, hinge to hinge across the front. The most useful single number on the list. Ideally it's close to the width of your face at the temples — a frame noticeably wider than your face slides about, and one noticeably narrower pinches.
Bridge is the gap between the two lenses, sitting over your nose. Small number, big consequences. Too wide and the frame sits low; too narrow and it perches high and leaves marks.
The shortcut: measure a pair you already own
Forget face-shape charts for a moment. The fastest way to buy well online is to find a pair you already like wearing and measure them.
Take any pair you own that fits comfortably. Lay them flat and, with a ruler, measure the full width across the front from hinge to hinge, then the width of one lens, then the gap over the nose. Three numbers, two minutes.
Those three become your reference. When you look at a new pair, compare them. Anything within two or three millimetres will feel much the same on your face. Five millimetres out is noticeable. Ten is a different frame entirely.
Many frames also carry these numbers printed on the inside of one temple, in the format 52-18-145 — lens width, bridge, temple length. If your favourite pair has them, you can skip the ruler.
If you're between two sizes
Go with the frame whose frame width is closest to your reference, even if the lens width is slightly off. Overall span is what holds a pair on your face; lens dimensions mostly change how it looks.
For a heavier frame with thick temples, the fit is less forgiving, so stay close to your measurements. Lighter, slimmer frames tolerate a few millimetres either way.
What about face shape?
It matters less than the internet suggests. The usual advice — angular frames for round faces, softer frames for square ones — is a reasonable starting point and no more than that. Plenty of people look best in exactly the frame the chart tells them to avoid.
Proportion is the part that actually holds up. A frame roughly as wide as your face, sitting level with your brow line, will look right regardless of which category anyone assigns your face to. Get the width right first, then choose the shape you actually like.
Two things that aren't about fit
While you're comparing, check for UV400 protection against harmful UVA & UVB rays. It has nothing to do with how dark the lenses are — a very dark lens without UV filtering is worse than no sunglasses at all, because it opens your pupils and lets more of what you're trying to block get through. Every pair we sell carries UV400.
Second, check what comes in the box. Frames live longer when they have somewhere to go between wears, and a case is the difference between a pair that lasts years and one that lasts a summer in a bag.
Still not sure?
Email us at sales@callenford.com with the measurements of a pair you already like, and we'll tell you which of ours comes closest. We'd rather spend a message getting it right than have you send something back.