Do you need pupillary distance for my prescription Swannies?

Your pupillary distance (PD) is necessary to made your custom prescription lenses. Your optometrist or eye doctor will usually have your PD on file and can provide this for you, or you can measure it yourself. Below is a guide on how to measure your PD, however we always recommend you have this done by a professional, for best results. 

WHAT IS PUPILLARY DISTANCE?

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

The PD is used to ensure that, when the lenses are cut for your frames, the center of the lens, which is the clearest part of the prescription, sits directly in front of your pupil. An accurate PD measurement helps optimize your viewing experience, and reduces eye strain.

INSTRUCTIONS
1. Stand about 8 inches away from a mirror.
2. Hold a millimeter (mm) ruler against your brow.
3. Close your right eye then align the ruler's 0 mm with the center of your left
pupil.

4. Look straight, then close your left eye and open your right eye.

5. The mm line that lines up to the center of your right pupil is your binocular
PD.

MEASURE WITH HELP FROM A FRIEND
1. Stand with a friend facing you (at about 8 inches apart), look straight ahead
and place the ruler on the bridge of your nose.
2. Cover your left eye and let your friend align the 0mm over the center of
your right pupil.
3. Cover your right eye and open the left, then let your friend note the
reading directly over your left pupil.
4. For measuring a PD with high accuracy, do it 3 times and take an average
number of them as the final PD measurement.
If you don’t have a millimeter ruler, you can search online to print one. Try
searching “printable mm ruler for eyeglasses.” Remember to print with 100%
scaling.

View our selection of custom prescription Swannies here.