Pupillary Distance (PD) is the space between pupils. All eyes are unique and spaced differently, this measurement makes sure your prescription lenses work for you. Without it, your vision may be blurry.

We have two ways to calculate your PD. The first is our PD calculator, which utilizes your computer's webcam or smartphone camera and a card with a magnetic strip to calculate your PD. The second is a printable PD ruler you can use to measure your own PD.




You'll need access to the camera on your laptop, tablet or mobile device. Next, grab a credit card or card with a magnetic strip. Light-colored cards with a contrasting dark strip work best. Lastly, find a room that is well-lit and avoid backlight. Turn your volume up to hear directions clearly.

Take Note

Take down your PD measurements. You will need this number later, to complete your prescription order. The PD tool will give you one number (ex: 64mm), just split that number in half for Left (32mm) and Right (32mm) Eye.


Click on the button below. Print and follow the instructions to use the PD ruler.


  1. Download then print to ensure it prints to scale. In print settings, use the ‘No scale’ or ‘Actual size’ setting. When printed at the correct scale, the card outline should be the size of a credit card.
  2. Have a friend hold the ruler horizontally against your brow, keeping your face straight. If you are alone a mirror will work just fine.
  3. Align the zero directly above the center of your right pupil. Without moving the ruler, follow it over to your left eye and read the measurement directly over the center of your left pupil.