PD (Pupillary Distance) is a measurement of the distance between your pupils. The PD is required so that we can make your glasses with the centre of the lens sitting directly in front of your pupil.
How to find your pupillary distance
Your optometrist will measure your PD when fitting your frames. If you have your prescription but don't know your PD and are trying to buy glasses online, you can measure it yourself quickly and easily.
Measuring your own pupillary distance
Stand 30cm away from a mirror and place a ruler against your eyebrows. Close your left eye and take note of the measurement at the inner corner of your left eye. Open your eye and then close your right eye, taking note of the measurement at the outer corner of your right eye.
Your pupillary distance is the distance between these two points.
If you need your pupillary distance for reading glasses, then subtract 3mm from your regular pupillary distance. For example, if your pupillary distance is 63mm, then your reading glasses pupillary distance is 60mm.
Measuring your pupillary distance with assistance
If you have someone in your household available, they can help to measure your pupillary distance.
Stand 30cm away from each other and have the other person hold a ruler against your eyebrows and place the 0mm marker at the centre of your left pupil. Then, have them measure to the centre of your right pupil.
This measurement is your pupillary distance.
As with measuring your own pupillary distance, if you need your glasses for reading, then subtract 3mm from the measurement to get your reading pupillary distance.