What is PD
pupillary distance (PD) is the distance in millimeters between the centers of your pupils. It is very important for accurately fitting your lenses to achieve vision acuity.
Average PD is about 62mm and most people fall within the 54 to 74 range. Sometimes your eye doctor will write your pupil distance for each eye (for example 34/35, called a monocular pupil distance). Or, the eye doctor may write the pupillary distance measurement as 69/65. This means that your pupil distance for distance vision (or DPD) is 69, and for near vision (or NPD, for reading eyeglasses) is 65.
How to measure PD?
While an optometrist's PD value is always recommended,your Pupillary Distance (PD) is something you can measure by yourself or with the help of a friend. If you chose to measure your own PD, please do so in millimeters.
To measure your Pupillary Distance (PD):
Place a millimeter ruler on the bridge of your nose.
Line up the starting point (0 mm) with your left (or right) pupil (the black dots in the middle of your eyes). This measurement is only accurate if you are looking straight ahead.
Looking straight into the mirror, hold the ruler (keeping it steady and parallel to the floor) and mark the location on the ruler of the other eye’s pupil. Or if someone else is reading the ruler they must be at the same height as you and be sure to hold the ruler steady and parallel to the floor.
Measure the distance in millimeters between the two marks. This is your PD Repeat the process two or three times for accuracy.
For those requiring bifocal or progressive lenses, we strongly recommend you get this information from your optician to ensure the accuracy of your glasses.