1.Wearing glasses? remove them and look at something 10-20 feet away.
It also helps to be in a well-lit area with a clean background.
2.Have your friend hold the PD ruler over your eyes
place the zero to the center of your right pupil.
3.Read the measurement.
The number directly over the center of your left pupil is your PD.
Have your friend repeat the measurement a few
times to make sure it’s correct.
Pupillary Distance ( or PD) is the measurement from the center of one pupil to the center of the other，it's used to help center a prescription correctly in your frames. You can normally find PD on your prescription. The average PD range for adults is 57-72 mm and for kids is about 43-58 mm.
How to Measure PD by Other People
How to Measure PD by Yourself
1.Stand about 8 inches or 20 cm away from a mirror.
It also helps to be in a well-lit area with a clean background.
2.Hold the ruler over your eyes.
keep the zero over your left pupil.
3.Close your left eye, and open your right eye while looking straight.
The number directly over your right pupil is your PD.
*For reading glasses, you can deduct 3mm from your PD measurement.
PD Measurement FAQs
How to read my PD values？
1.Dual PD is notated as a single number such as "63", means the total distance between your pupils.
2.Single PD is the distance from the bridge of your nose to your pupil on each side. It is notated as two numbers around 30mm such as 31 and 32.
3.Sometimes PD is notated as "61/58". 61 is your distance PD .While 58 is your reading PD.
How do you measure your PD without a ruler?
An easy way to measure your PD is with a credit card.
Does my PD have to be exact?
Your PD should be accurate. If your lenses are not centered correctly, they may be uncomfortable to wear. Small errors may not cause problems, but it's best to be as accurate as possible.
Where is my PD on my prescription?
Your PD will be in the "PD" or "Pupillary Distance" section of your prescription. This is usually separate from the "grid" part of the prescription where the doctor writes the main prescription information.How to Read Your Prescription
Does PD affect frame size?
Your interpupillary distance affects the shape of your lenses, but not the size of your frames.
Does PD change over time?
When a person is young, the pupillary distance will change because the body is still developing. Once they mature and stop growing, their interpupillary distance changes little, if at all.