0 Favorites
Your favorites

You have no favorite items.


There are no items in your cart.

Measuring Pupillary Distance (PD)

Before you place an online order for eyeglasses, you need to know your pupillary distance (PD). This measurement—which is the distance between the pupils of your eyes—is needed to correctly center the lenses within the frame.

Although your PD is often measured by your eye doctor during your exam, PD measurements are not always listed on your prescription—but, no worries, it's easy enough to obtain using a ruler and a mirror.

Note: These instructions are for getting your Distance PD measurement. If you require prescription bifocal glasses then you will also need your Near PD, which is calculated by subtracting 3mm from this Distance PD measurement.

If you have any questions, contact our Customer Service Team to help you out.


  • Hold a ruler against your brow
  • Align the ruler's 0 mm mark with the center of the left pupil
  • The millimeter line that aligns with the center of the right pupil is the PD

Adults generally have a PD within 54-68 mm, while children have a PD within 41-55 mm.

PD Measurement Ruler

Related Articles

How to Read Your Eyeglass Prescription

Learn how to read and enter your eyeglass prescription when placing an order.

Why an Annual Eye Exam is Important

Maintaining good eye health goes far beyond making sure your vision isn’t blurry. Eye doctors conduct a wide variety of tests to examine and assess the quality and health of your vision, as well as identify any health problems that could result in vision loss.

Discount Glasses
+1-888-264-5400 customer service
social link social link social link