Pupillary distance (or PD) refers to the distance between your two pupils. It’s necessary to center a prescription in your frames for clear, accurate vision. You can use our online tool here to measure your PD using just a webcam or smartphone camera. Review the steps below before beginning.

1. Take off glasses. Make sure the image is well-lit.
It also helps if the background is clean.

2. Adjust your screen, look at the camera.
The angle of the photo is straight-on.

3. Place any card with a magnetic strip under your nose, then take the photo.
The magnetic strip forms a straight “card moustache”

What is Pupillary Distance?

Pupillary Distance (or PD, for short) is the distance between the centers of your pupils.

Why Do You Need to Know?

In order to best fit you with your new glasses, it’s important for us to know your PD. This tells us where your gaze falls in your lens. Your pupillary distance determines where your “optical center” lies. For the majority of adults, PD is roughly 54-74 mm. In children, PD typically ranges from 43-58 mm.

What is Single vs. Dual Pupillary Distance?

Your single glasses PD is one number that describes the distance between the center of one pupil to the center of the other. This can be used for prescription glasses, but not reading glasses. For those, you need to measure your Dual PD.

Your dual glasses PD is also called your monocular PD and consists of two numbers. The first number always refers to the right eye and the second describes the left eye.

What is Near PD and Why Do I Use It?

Near glasses PD is important to calculate if you are looking to order reading glasses. You can easily calculate this from either your single PD or your dual PD. You simply subtract 3 mm from your distance PD. If you are beginning with dual PD, you will subtract 1.5 mm from the measurement for each side.

How Do I Find My PD?

Usually, your doctor will give you your PD measurement. But, if this somehow is forgotten or you aren’t sure its an accurate measurement, we can suggest three options to help you measure PD on your own.

Measure PD with a Ruler and a Mirror

Stand 8 in away from a mirror.
Hold a ruler against your browline.
Close your right eye
Align the ruler’s 0 mm with the center of your left pupil.
Look straight ahead.
Close your left eye and open your right eye.
The mm line that lines up to the center of your right pupil is your PD.
You now have a single PD measurement!

TIP: Measure 3-4 times and record your findings. Take these measurements at various times during the day. Believe it or not, your pupillary distance can change multiple times throughout the course of the day. Then, use the average of these measurements. That way, you can ensure consistency and accuracy!

TIP: Have a friend give you a hand (or two)!

Keep both eyes open.
Look straight ahead.
Have your assistant sit or crouch in front of you, so they are out of your line of vision.
Look at something 10-20 feet away above his/her head.

Eyes off your friend!! *This part is hard, but you can do it - and it’ll give you a more accurate reading.*

Print Tool to Measure PD

If you don’t happen to have a ruler handy, we have one for you! And it’s double-sided, making it easy for not just a friend to read, but also for you to read in the mirror. How nifty is that?!

Print our handy tool.
Check the scale by lining up the ruler to one of your own - or check in with the standard size credit card.
Fold the ruler on the dotted line.
Position yourself at arm’s length from a friend OR 8 in from your mirror.
You now have a single PD measurement!

TIP: Measure 3-4 times and record your findings. Take these measurements at various times during the day. Then, use the average of these measurements. That way, you can ensure consistency and accuracy!

TIP: Get help from a friend - same rules as above (EYES OFF YOUR BESTIE!)

Use Our Pupillary Distance App to Measure

You can use our app to help measure PD when ordering new glasses. There’s no need to download an additional app as the feature is browser-based. You can get a quick and accurate reading in just a few easy steps! Follow the instructions above.

Now What?

Now that you’re able to provide us with an accurate PD measurement, we can get to work making your very best prescription eyeglasses so you can see clearly and beautifully - and look great, too! We have a huge selection of beautiful, designer frames and scratch and smudge-resistant lenses with quality features like blue-light blocking coating. You can browse our collection by color, frame shape, and even by frame type as relates to your facial shape. We are here to help your absolute best - so we make choosing your next pair of prescription glasses easy and fun! Take a look and let us know what you think!