Pupillary Distance is the distance between the centres of the pupils in each eye, measured in millimetre (mm). PD measurement is required in making your glasses. Most adults have a PD of 57 – 68 mm. In some cases, PD is represented in 2 numbers (for example, 31/31.5). They are the distances between the centre of your nose to each pupil centre. PD is often part of your prescription from your eye care professionals.

Step 1: Enlist the help of a trusted friend and a ruler (mm: millimetre)

Step 2: Look straight ahead, place a ruler on the bridge of your nose

Step 3: Measure the distance from the left pupil to right pupil (in mm)

Step 4: Repeat the measurement 2 to 3 times to make sure that it is accurate