Pupillary distance (PD) measures the distance between the centers of your pupils and is used to center a prescription lens accurately in your frames. From childhood to adolescent years, PD can change rapidly during growth spurts, so regular measurements are recommended. As we get older, PD tends to stabilize but still can change over time due to various factors such as changes in facial structure, muscle tone, etc. Ask your doctor to measure this for you on your next exam or you can have your optician measure it for you. If you are buying your new glasses online and need this information, there are many online tools that can help you. If you would like to figure this out on your own watch our video or read the instructions.
- You’ll need a ruler with millimeter measurements and a mirror or a friend.
- If using a mirror, try to look straight ahead and into the distance as you measure. If a friend is taking your measurements, try to look past them (straight ahead) into the distance to avoid the result being too narrow.
- Rest the ruler against the bridge of your nose and line up the middle of your left pupil with the zero line on the ruler. You can now measure the distance between your pupils.
- Measure across to the middle of your right pupil, still looking into the distance. The average PD for adult women ranges from 46mm to 65mm; adult men ranges from 59mm to 74mm.
- Repeat these steps two to three times to get a consistent number.