How to measure your PD

Glasses Of The Day - PD Measuring

We’ve designed 5 easy steps you can do yourself to measure your PD. You will need a ruler and a mirror.

Step 1

Stand about one arm’s length away from your mirror

Step 2

Hold the ruler horizontally across your forehead in line with your eyebrows.

Step 3

Ensure your head is straight and close your right eye. Line up the start of the ruler (0mm) with the centre of your left pupil.

Step 4

Making sure you are looking straight forward, close your left eye and open your right eye.

Step 5

Read off how many mm line up with the centre of your right pupil and this is your PD. Repeat the 5 steps one more time to get an accurate measurement.


If your glasses are for reading you should subtract 2mm from your PD. Eg if the PD you measured was 58mm, the PD you should input for reading glasses is 56mm.