What is Pupillary Distance (PD)?

Pupillary distance (PD) is the distance between the pupils of the eyes. It is an important measurement when purchasing eyeglasses, as the lenses need to be aligned with the center of your pupil to provide clear vision. Measuring pupil distance accurately ensures that the optical center of the lenses is in the right position for your eyes. 

Measuring your own PD

If you’d rather measure your PD yourself, or get a friend to help you out,have a look through our step-by-step guides.

1.Stand about 30cm away from a mirror

2. Looking at yourself, hold a ruler up against your eyebrows

3. Close your right eye, then line up the ruler so that 0mm is in line with  the middle your left pupil

4. Look straight ahead again and then open your right eye and close your left

5. Your pupillary distance measurement will be the figure that linesupwith the centre of your right pupil

Measuring a friend’s pupillary distance

• To measure someone else’s PD, have them look at something around 20 feet away from them with both their eyes open.
• Using a ruler, line up the 0mm mark with the centre of one pupil, then measure to the centre of the other.
• You just need to make sure that you stay out of their line of sight, they keep looking straight ahead with their eyes as still as possible, and that they don’t look at you while you’re measuring.
• Do this a few times to make sure the measurement you get isconsistent. The average pupillarydistance for adults is usually between
  54-74mm.