Occhiali da sole Kador Big 1

How to read your glasses measurements

On the inside of the temple of almost every pair of glasses there is a series of numbers, for example 52□18 140. They are not random codes: they are the frame measurements, in millimetres, and they are the safest way to buy glasses online in the right size.

Where to find the measurements

Open your glasses and look at the inner side of the temple, in most cases the left one: that's where the model code, the colour code and the three measurements are printed.

Left temple · inner side CK4362S 001 52□18 140 Model Colour Size hinge

What the three numbers mean

Lens width · 52 mm Bridge · 18 mm
  • Lens width (52): the width of one lens, measured horizontally. It is the measurement that, more than any other, determines whether a pair of glasses is small, medium or large.
  • Bridge (18): the distance between the two lenses, i.e. the part that rests on the nose. A bridge that is too narrow pinches, one that is too wide makes the glasses slide down.
  • Temple (140): the total length of the temple, from the hinge to the tip that goes behind the ear.
Temple · 140 mm hinge bend behind the ear

The □ symbol between lens width and bridge means the measurements are taken with the international standard system. Sometimes you will find a dash instead.

The other codes on the temple

You will usually also find the model code (for example CK4362S) and the colour code. Keep them handy if you need a spare part or want to buy the same model again. Sunglasses often also show the filter category, from 0 to 4: category 3 is the most common and is suitable for bright summer light.

The same model in two sizes

Many glasses come in more than one lens width. The Kador Big 1, for example, is available in lens width 56 and lens width 58: same bridge (15) and same temples (148), but lenses 2 mm wider in the 58 version. It doesn't sound like much, but you can see the difference on the face.

How to use the measurements to buy online

The easiest method is to take a pair of glasses that fits you well and read its measurements. Then compare them with those shown on the product page:

  • lens width: up to 2 mm more or less is fine
  • bridge: up to 1-2 mm difference
  • temple: up to 5 mm difference

If you don't have a reference pair, a useful rule of thumb: lens widths of 48-51 generally suit small faces, 52-55 medium faces and 56 and above large faces.

48 – 51 52 – 55 56 and above Small face Medium face Large face Indicative lens width by face width

Not sure about the size?

Write to us before you buy with the model you are interested in and the measurements of your current glasses: we will tell you if it's right for you. And if your glasses have a broken temple or a lost nose pad, take a look at our spare parts page.

Savio Lattanzio, optometrist, Ottica Lattanzio – Trinitapoli

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