It’s not hard to measure your PD, or pupillary distance.
1. Stand about 20 cm (8 inches) from a mirror and hold a ruler against your eyebrow.
2. Close your right eye, and put the start of the ruler (at 0mm) over the center of your left pupil. 3. Look straight ahead, then close your left eye and open your right eye.
4. The distance between the center of your right pupil and your left pupil is your PD or pupillary distance.
Most adults have a pupillary distance between 54-75mm. Kids’ PD can range from 43-58. If your measurements are outside of these ranges, you’ll want to make sure you’ve lined up the ruler correctly. However, it’s always good to double-check the measurements.
Your pupillary distance doesn’t have to be 100% accurate. Your eyes can easily adjust to a small range of error. But if the PD measurement is too off, you won’t see as well since the PD is the optical or visual center of your eye.