How to Measure Your Pupillary Distance or PD
Pen / Marker.
Stand straight in front of a wall mirror, and place the ruler on your nose.
- The starting point is the centre of the pupil of either eye, right or left.
- At this point, make sure you have one eye closed and locate the centre of your open eye.
- Line up the Zero(0) of the ruler with the centre of the pupil in the open eye.
- Next, open the eye which was closed, and close the eye which was open. Now, all you need to do, is read which (mm) number lines up with the centre of the pupil in theeyr which is now open. You can use the marker to make a note on the ruler to help you if you would like.
- The distance between the centre of the pupils in your eyes, is the PD measurement.
Another way to measure
As pupils are quite dark, it is sometimes difficult to know where the exact centre is. One method which ensures you will get the right measurement is by using the border between the white part of your eye, (sclera) and the black pupil.
Close one eye and line up the Zero (0) of the ruler to either the inner or outer pupil edge, remembering to always have one eye closed, and read across to the opposite pupil edge.
Always measure outside pupil edge to inside, or inside to outside, never outside to outside, which would mean that the PD measurement would be too large, or inside to inside, which would mean the PD measurement would be too small.
As a routine, PD is not added to your prescription, but you can request it when you get a copy of your prescription.
Don’t worry if you do not have this as its easy to measure.