Pupillary distance (PD) is a crucial measurement in optometry and eyewear fitting. It refers to the distance between the centers of your pupils and is essential for ensuring lenses are properly aligned for clear, comfortable vision.
The average adult PD ranges from 54 to 74 millimeters. There are two types of PD measurements: binocular PD and monocular PD. Monocular PD is more precise and is especially important for progressive lenses.
To measure your PD at home, you will need a millimeter ruler and a mirror. Stand about 8 inches from the mirror and hold the ruler against your brow. Close your right eye and align the zero to the center of your left pupil. Then close your left eye and open your right eye. The number that lines up with your right pupil is your PD.
For the most accurate results, have someone else measure your PD while you look at a distant object. Repeat the measurement a few times to ensure accuracy.
An incorrect PD measurement can cause eye strain, headaches, and blurry vision. Always make sure your PD is measured accurately, whether by your optometrist or carefully at home.