Determine your pupillary distance (PD).

Pupillary distance (PD) or interpupillary distance (IPD) is the distance measured in millimeters between the centers of the pupils of the eyes. This measurement is different from person to person and also depends on whether they are looking at near objects or far away. 

Measuring pupillary distance

Different methods for measuring exist but accurate measurement can usually be determined by an ECP during an eye examination. This is normally done with a small millimeter ruler referred to as a “PD stick” or with a corneal reflex pupillometer, which is a machine calibrated to help the optical professional more accurately measure the pupillary distance. But technology has made it much simpler and allows you to do it yourself, or even better, with a friend.

Use the button below to download and print your PD ruler and Instructions.

Measure Your Pupillary Distance (PD)
Measure your pupillary distance with a ruler from Romi Eyewear.
Numbers inside the eyeglass frame indicating the size.

Determine your current frame size.

If you have a pair of glasses that fit you well, we can use those measurements to help find your perfect fit.

Inside the arm piece (temple) or behind the nose bridge you will see 3 numbers which are your frame measurements.
For Example 52-17-140 indicates your eyesize, bridge size and temple length in millimeters.

Staying within 2 mm of your current eyesize, 1 mm of your bridge size and 5 mm of your temple width is acceptable to finding the perfect fit.

If you do not have a current pair of glasses to work with the following guide lines are best:

  • Small/Kids Frame …… Eyesize of 50mm or less
  • Medium Frames….. Eyesize of 51-54mm (most common frame option)
  • Large……Eyesize of 55mm and above