How to measure the lens size of your glasses

The lens size is the width of the lens in your glasses, measured in millimeters. It is the key piece of information for buying replacement lenses that fit: you will almost always find it printed on the inside of the temple and, if not, you can measure it yourself with a ruler in under a minute.

Knowing the lens size also helps you choose the frame size that best suits your face. Bear in mind, though, that two pairs of glasses with the same lens size can have very different shapes and styles: the lens size tells you the width, not the shape.

Where the lens size is printed

Before you get the ruler out, look at the inside of the temples. On a pair of Ray-Bans you will find something like “RB3025 001 58□14”. Each part means the following:

RB3025: the model.
001: the frame color code.
58: the lens size, that is, the width of the lens in millimeters.
14: the bridge width, the distance between the two lenses.

A third number, the temple length, is often shown too. On Oakleys the model reference is also usually on the inside of the temple.

How to measure the lens size with a ruler

If the markings have worn off or you can’t find them, you can measure the lens directly.

Take a ruler or tape measure marked in millimeters.
Rest the glasses on a table with the lenses facing you.
Place the ruler horizontally across the widest part of the lens.
Measure from the far left edge to the far right edge of the lens, counting only the part inside the frame. Don’t include the outer edge of the rim.
Write down the measurement in millimeters: that is your lens size.

Tips for an accurate measurement

Measure both lenses; they should give the same result.
Use a rigid ruler and look at it straight on, not at an angle.
Remember that some manufacturers round the lens size to whole numbers, so your measurement may differ slightly from the official one.
Whenever you can, check your measurement against the specifications for your model.

Why the lens size matters so much

Many models are made in several sizes. If you order a replacement lens for the right model but in a different size, it won’t fit your frame. That is why, on our product pages, you will always have to choose the size along with the color.

The same goes for temples: the length shown in the markings helps you order a temple that fits just like the original. If you are ever torn between two very close sizes, don’t guess; it is better to confirm the reference before buying and avoid a return.

Common measuring mistakes

Including the edge of the frame. The result comes out several millimeters too big.
Measuring diagonally or vertically. The lens size is the horizontal width of the lens.
Confusing the lens size with the bridge. In the markings, the lens size is the first number and the bridge the second.
Measuring in inches. Eyewear measurements are always given in millimeters.

Frequently asked questions

Is the lens size the same on all glasses of a given model?

Not always. Many models are made in several lens sizes, which is why you need to check the measurement of your own glasses.

What if my measurement doesn’t match any size?

It is probably due to rounding or a slight inaccuracy when measuring. Write to us with a photo of your glasses and the ruler next to the lens and we will help you identify the size.

Do I also need the bridge and temple measurements?

To buy lenses, the model and lens size are all you need. The bridge width and temple length help you identify the frame and choose replacement temples.

What warranty do the lenses have?

All our lenses, both original and compatible, come with a 3-year warranty against manufacturing defects.

Find your replacement lenses

With the model and lens size, you are ready to search for your lenses. We offer original Ray-Ban replacement lenses, a more affordable alternative in compatible Ray-Ban replacement lenses and original Oakley replacement lenses. Standard shipping is free on orders over $ 50.53. If you have any questions, write to us and we will help you by email.