Measuring the pupil distance or pupillary distance is one of the important things to do before you shop for a new pair of prescription glasses online.
PD refers to the distance between the center of the pupils that is measured in millimeters. You can measure it on your own or an eye care expert can do it for you.
You will an exact pupil distance to ensure proper placement of lenses on the frames. This centers the prescription right in front of the pupils to have the clearest and most exact vision with your brand new pair. Inaccurate PD may lead to unwanted headaches and eye strain.
As much as possible, it is recommended to get your PD measurement from an eye care expert. However, you don’t need to worry if this is not part of your glasses prescription. You can easily measure PD on your own.
All you have to do is take your time and try doing it at least two times to make sure that it is really accurate.
Check out the following guide for measuring the pupil distance at home
- You need the help of a friend or a mirror and a ruler with millimeter measurements.
- If you will use a mirror, make sure you look into the distance and straight ahead while measuring. If your friend will take your measurement, you should try to look straight ahead or past them into the distance to ensure that the result is not too narrow.
- Place the rule against your nose bridge then line up the center of your left pupil with the ruler’s zero line. You could now proceed to measuring the pupil distance.
- Measure across to the center of the right pupil while still looking to the distance. For adult women, the average pupil distance can range from 46mm up to 65mm. Pupillary distance can range from 59mm to 74mm for adult men.
- Repeat the above steps twice or thrice to get a more consistent number.
An important tip here is if you are using a ruler in centimeters, this can be converted online. However, measuring your PD should never be done in inches. This may result to a wrong conversion with an inaccurate measurement. Measuring your PD incorrectly will make it impossible to get the correct lens placement.
Where Can You Find Your Pupil Distance?
When you buy your new pair of glasses, it is a must that all of your prescription details are handy for the process to be easy and quick.
If you visited your eye care provider recently to get an eye exam, your PD can be found on the prescription. If this is not provided, there are two possibilities here.
First is that there is a chance that the prescription is meant for contact lenses that may be different from eyeglasses. Measurements between glasses and contacts are different.
Second is that if you cannot find your pupil distance even if you have prescription glasses, the number might be missing since your optician or optometrist didn’t give it to you since they will take care of this when you buy in store. It is recommended to get in touch with your eye doctor to check if your file contains the measurement before you start measuring the pupil distance on your own.