Face shape and frame fit are two different questions. Knowing you have a round face tells you that angular frames suit you — but it doesn't tell you whether a specific pair of angular frames is the right size for your face. A correctly-shaped frame that's too wide or too narrow will still look and feel wrong.
If you haven't identified which frame shape suits you yet, start with the face shape to glasses shape guide. This page picks up from there — once you know the shape, here's how to get the fit right too.
Measuring Your Face Width at Home
You don't need special tools. A soft tape measure or a ruler held across your face gives a usable measurement:
Find your temple width
Measure straight across your face at the temples — the widest point behind your eyes, roughly where glasses arms would sit.
Record it in millimetres
Frame measurements are always in millimetres, not inches — converting your measurement now saves confusion when comparing to frame specs later.
Add a small margin
A well-fitted frame typically sits within about 2–4mm of your measured temple width on each side — not flush against it.
Reading the Numbers on a Frame
Every pair of glasses has three numbers printed on the inside of the temple arm — usually something like 52-18-140. Once you know what they mean, you can compare any frame to your own measurements before buying.
| Number | What It Measures | Typical Range |
|---|---|---|
| Lens width | Width of a single lens | 44–58mm |
| Bridge width | Gap between the two lenses, over the nose | 14–24mm |
| Temple length | Arm length from hinge to ear tip | 120–150mm |
Frame width (lens width × 2 + bridge width) is the number to compare against your temple measurement from the previous section.
Common Fitting Mistakes
Choosing the right shape in the wrong size
A round face genuinely suits angular frames — but an angular frame that's too narrow pinches at the temples and looks undersized regardless of how well the shape suits you.
Ignoring bridge fit
A bridge that's too wide lets glasses slide down the nose constantly; too narrow pinches. Bridge fit is often overlooked in favour of lens width, but it affects daily comfort the most.
Temple arms too short or too long
Arms that are too short pull the frame forward and press behind the ears; too long and the frame sits loosely and slides. This is the dimension most people forget to check when buying online.
Still Need to Find Your Frame Shape?
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Frequently Asked Questions
- What do the numbers on the inside of glasses arms mean?
- A typical marking reads three numbers, e.g. 52-18-140. The first (52) is lens width in millimetres, the second (18) is bridge width, and the third (140) is temple arm length. Together these describe fit far more precisely than "small," "medium," or "large."
- How much wider should glasses be than my face?
- As a general guideline, frame width should be within a few millimetres of your face width at the temples — neither noticeably narrower, which pinches, nor noticeably wider, which overhangs. This is independent of which frame shape you choose.
- Do I need a professional fitting, or can I measure at home?
- For prescription glasses with a specific optical centre requirement, a professional fitting is worth it. For general frame-width and style shopping, the at-home measurement method in this guide is accurate enough to avoid the most common sizing mistakes.
- Can I fix frames that are slightly too big at home?
- Minor adjustments — bending the temple arms slightly, or adjusting nose pads — can be done carefully by hand. Anything beyond a minor adjustment is best handled by an optician to avoid cracking the frame.
