What is PD?
PD means “pupillary distance,” which is the distance between the center of each pupil. This measurement is used to determine where you look through the lens of your glasses.
If you want to order eyeglasses online, you can either ask your optometrist for your PD or measure it yourself. If obtaining your measurement from your optometrist isn’t possible, no worries—you can measure it from home using ruler!
How to Measure Your PD At Home？
Can I just guess my PD?
Pupillary distance must be accurate for prescription glasses to properly work. Guessing will result in you not being able to see out of your prescription glasses properly and you will have to order a new pair with the correct pupillary distance.