Pupillary Distance (PD)

You'll need to know your PD if you want to order glasses from EyeBuyDirect. Don't worry if your glasses prescription doesn't include your PD, we can show you how to measure it by yourself.

PD, or pupillary distance, refers to the distance in millimeters between the center of one pupil to the center of the other. Having a correct PD on your glasses prescription insures that you are looking through the ideal spot in your lenses. If this number was not provided on your prescription by your eye care professional, you can measure it yourself.

*Note that the average PD is between 57 and 65mm. For bifocal and progressive lenses, two PD values are needed. In these cases, EyeBuyDirect recommends getting your PD directly from your eye care professional.

Measure PD your self

1. Print our downloadable PD ruler

2. Place the ruler directly over the center of your right pupil so that the ruler is horizontal. Place against forehead for added stability. Stand in front of a mirror, or ask someone else to measure for you.

3. While looking straight ahead, measure the distance from the center of your right pupil to the center of your left pupil.

4. Repeat a couple of times for accuracy and use an average for your final measurement.

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