Eyewear fit
Find the frame size that fits your face
Two things have to be true at once: the front should be about as wide as your face, and the frame's own PD should sit close to yours. For most faces they pull against each other. This searches real manufacturing sizes for the best compromise and tells you how much compromise was involved.
Edit either number and the sizes below update as you type. Already know your PD? Measure it properly here — a camera capture averaging sixty frames beats the quick reading this page takes.
| Marking | Front width | Frame PD | Decentration |
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Found a frame you like? Check its exact numbers.
The two constraints, and why they fight
A spectacle frame has to satisfy two independent requirements, and nothing guarantees that one frame satisfies both.
The first is mechanical. The front of the frame needs to be about as wide as your face at eye level. Too wide and it has nothing to grip, so it slides down your nose whatever the temples do. Too narrow and it presses on the sides of your head, leaves marks, and levers itself forward.
The second is optical. Lens width plus bridge width gives the distance between the two lens centres — the frame's own PD. The further that sits from your pupillary distance, the further each lens must be shifted for its optical centre to land in front of your eye. Up to about three millimetres per lens this is invisible. Past five it shows, and how much it shows scales with your prescription.
Why they cannot always both be met
Face width and pupillary distance are only loosely related across a population. Two people with identical 138 mm faces can have PDs of 58 and 68, a full centimetre apart. Frames, meanwhile, are manufactured in a fairly narrow band of proportions, because manufacturers make what sells in volume.
So the wide-face, close-set-eyes combination is genuinely hard to fit. Every frame wide enough for the face has its lens centres too far apart, and every frame with the right lens centres is too narrow to sit properly. This is not a flaw in anybody's face. It is a gap in what gets manufactured.
When that happens, this tool says so rather than picking one constraint and quietly ignoring the other. And it points at the actual solution, which is that a dispensing optician can order a smaller eye size on a longer temple.
How the search works
Every combination of lens width from 44 to 58 mm and bridge from 14 to 22 mm is a frame that somebody makes. For each one, overall front width is two lens widths plus the bridge plus about 12 mm for the endpieces and hinges.
The tool keeps only the combinations whose front lands within four millimetres of your measured face width, then ranks what survives by how little decentration each needs, and shows one option per bridge size so the list offers real alternatives rather than nine near-identical frames.
That last detail is the useful part. At a fixed front width, moving a millimetre from the bridge into each lens pushes the lens centres apart and raises the frame PD. So if your PD is wide for your face you want a wider bridge, and if it is narrow you want a narrower one. This is why two frames both marked 52 can fit completely differently, and why the bridge number deserves as much attention as the lens number.
Measuring face width honestly
The camera measures from the outermost visible face landmarks at eye level, scaled off your iris exactly as the PD tool does. It carries one systematic bias worth stating: those temple points sit where the face begins curving away from the lens, so a front-on photograph foreshortens them slightly and the reading runs a little narrow.
Pupils do not suffer from this, because they face the camera directly, which is why the PD figure from a photo is more trustworthy than the width figure. If you have a tape measure, check the width across your face at eye level and type the real number in. A few millimetres moves which sizes qualify.
What this deliberately does not do
It does not tell you which frame shape suits your face. Round faces suit angular frames, square faces suit round ones, and so on through a set of rules that are styling convention with no measurable basis behind them. Presenting that as the output of a calculation would give it an authority it has not earned.
Dimensions either fit or they do not, and that is a question arithmetic can answer. Whether a frame suits you is a question about taste, and you are better placed to answer it than we are.
This tool performs arithmetic on measurements. It is not a dispensing service. For progressive or bifocal lenses, strong prescriptions, prescriptions containing prism, or children's eyewear, have the frame measured and fitted by a qualified dispensing optician — those cases need a fitting height and a pantoscopic tilt that no front-on measurement can supply.
Questions people ask
- How do I measure my face width without the camera?
- With a tape measure or ruler held against a mirror, measure straight across your face at eye level, from the outer edge of one temple to the other — the widest visible points, level with your eyes. Keep the tape horizontal. Most adults land between 128 and 150 mm.
- Why does the camera reading come out slightly narrow?
- The temple points sit where the face starts curving away from the camera, so a front-on photograph foreshortens them. Pupils do not have this problem, because they face the lens directly. Treat the camera face width as a good starting estimate and verify it with a tape measure if you can — a few millimetres changes which frame sizes qualify.
- Why does it suggest a narrow bridge with a wide lens?
- Because for a given overall front width, shifting millimetres from the bridge into the lenses pushes the lens centres outward, which raises the frame's own PD. If your PD is narrow relative to your face, the opposite applies and a wider bridge helps. The tool is trading one against the other to minimise how far each lens has to be decentred.
- My face width and PD seem to want different frames. Is something wrong with my face?
- No. Face width and pupillary distance do not scale together across people, and frames are manufactured in a fairly narrow band of proportions. A wide face with a close-set PD is common and genuinely awkward to fit off the peg. An optician can order a smaller eye size with a longer temple, which resolves it properly.
- Does this tell me which frame shape suits me?
- No, and that is deliberate. Shape advice — round faces suit angular frames, and so on — is styling convention with no measurable basis, and dressing it up as a calculation would be dishonest. What this does is arithmetic on real dimensions, which either fit or do not.
- Can I use this for sunglasses?
- For fit, yes: the same three numbers are marked on sunglasses and the same width arithmetic applies. Decentration matters much less, since most sunglasses have no prescription power, so prioritise the front width match and treat the frame PD column as informational.