Pupillary Distance

Let's measure your PD!

Your PD is the distance between your pupils. It helps us fine-tune your lenses to your eyes. Don't see it on your prescription? Our simple tool will provide you with an accurate PD in seconds.

By using our Pupillary Distance Measurement Tool, you agree to an image of your face being collected with your webcam.

Your pupillary distance (PD) is the distance between the centers of your pupils, in millimeters. We use it to center each lens in front of your eye, so you look through the optical center of the lens. Every prescription lens order needs it: single vision, progressive, bifocal and readers alike.

Check your prescription first

Many prescriptions list the PD. It may be one number (for example 63) or two (for example 31.5 / 31.5, right eye first). If yours shows two numbers, tick "I have two PD values" when you order and enter both. If it shows a distance PD and a near PD, use the distance PD. Your eye doctor or optician measured it at your last exam and will usually give it to you if you ask.

Measure it with your camera

If your PD is not on your prescription, our camera tool measures it in a few seconds. Use the "Measure my PD" button at the top of this page, or the "Measure with your camera" button in the pupillary distance step when you choose your lenses, and the result is filled in for you. The tool needs a webcam or phone camera in a current version of Chrome, Safari, Edge or Firefox. Take your glasses off, face a window or a lamp so your face is evenly lit, and keep a credit-card-sized card handy: the tool may ask you to hold it against your forehead for scale.

Tips for an accurate PD

  • Look straight at the screen and hold still while the tool measures. Glancing away or tilting your head can throw the reading off.
  • Measure children rather than guessing: a child's PD changes as they grow. Most adults measure between 54 and 74 mm, most children between 43 and 58 mm.
  • Not sure about a number? Contact us and our opticians will help.