How to Measure Your PD for Glasses

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.
Note: If we have made you glasses before, your PD measurement may already be on file.

There are three different ways below to measure your PD.

I. You can measure your PD with a marker. Try to use a non-permanent marker.

II. You can measure your PD on your own at home.

III. You can meaure your PD with the help of your friend or relative.

I. Measuring your PD with a marker and your glasses.

II. Measuring your PD on your own.

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.

III. Measure your PD 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 print the one below. Remember to print with 100% scaling.