What is pupil distance (or PD for short)? It is the distance in millimeters from the center of the pupil of the right eye to the center of the pupil of the left eye. To give you optimum vision, this measurement must be accurate so that the center of the lens is in line with the center of your eye.

To get your pupil distance, you need to ask your optician for this measurement at the time of your eye test, measure it yourself with a mirror, or ask a friend to help you. If your optician measures your PD, make sure it is marked on your prescription.

You can measure your own PD using a mirror and a millimeter ruler.

1. Place the ruler flat against your forehead and with your right eye closed, line up the zero on the ruler with the center of your left pupil.
2. With your left eye closed, take a reading of the ruler at the center of your right pupil.

If you have difficulty seeing what you are doing, then use a magnifying mirror. If it is easier, line up the outside of the iris of one eye with the inside of the iris of the other eye and use that measurement.

** For your convenience, we have created a printable millimeter ruler (.pdf) for you to     download and use for pupil measurements.

We need your distance PD on the order form if you are ordering distance or bifocal glasses, and your near PD on the order form if you are ordering reading glasses. Your near PD is 3mm less than your distance PD, as your eyes move closer together when you read. For adults, the typical PD measurement is from 54 to 66. If you do not supply your PD measurement, we will set distance optical center at 65mm for men and 63mm for women.

Only one measurement is necessary. Any adjustments needed for reading or bifocal glasses will be made by us.

If you enter incorrect prescription information such as an inaccurate papillary distance measurement, you may not be able to see well with your new glasses. We cannot be responsible for mistakes in prescription information provided by you or your optometrist or ophthalmologist. We guarantee that your prescription safety glasses will be made exactly to the specifications that you provide.