The secret to ordering a perfectly fitting pair of eyeglasses online is simple: know your frame size. The frame size of eyeglasses and sunglasses uses the same three key measurements:
The two most common ways to measure your frame size are to find the size of your current, well-fitting glasses, or to use a soft measuring tape, with millimeter measurements, to find your measurements.
Sunglasses tend to be larger than eyeglasses, so your sunglasses size will most likely be different than your eyeglasses size, even though they both use the same measurements. With sunglasses, you have more freedom to choose within a wider range of sizes, since the fit does not need to be as precise. Generally, glasses will still fit within 2-3 millimeters of a “perfect fit.” So while the perfect fit is ideal, if your ideal frame is only available in a size that’s within that 2-3 millimeter range, you may still be able to wear them comfortably.
Every pair of glasses is a little different, so the size information may not always be located in the same place.
Look on the inside of your current frames. You will find the size information stamped either on the temple, like this example:
Or on the bridge, like on this metal example:
or like on this plastic nose bridge:
On some models, you may also find the size stamped on the earpiece.
There can be quite a few different kinds of numbers and markings inside your frame, and not all of them are relevant to the size.
The eye size and bridge size are often located next to one another, sometimes separated by a square box icon. The temple size may immediately follow those two sets of numbers, or have some other info in between.
You are looking for (2) two-digit numbers and one three-digit number. Here's how to identify them:
Eye Size: a two-digit number in the 40 - 62 range
Bridge Size: a two-digit number in the 14 - 24 range
Temple size: a three-digit number in the 120 - 150 range
The eye size is the most important number to pay attention to. Depending on the style of frames you choose, you can go up or down by one and still find a decent fit.
A set of capital letters and numbers grouped together is generally the model number or the frame color/style number(s).
In the image above, "VPR 020" is the frame model number while "EAJ-101" is the color/style number.
International: +1 512 402 8557
Also see: Reading Glasses | How to Measure Pupillary Distance or PD | Lens Color Guide | Understanding Your Prescription