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How to measure your Pupillary Distance (PD)

If you want to order glasses online from Stanton Optical you will need to know your Pupillary Distance (PD). Here are a few definitions and tips for you to be ready to purchase your dream glasses from us with your PD ready!

So, what is Pupillary Distance?

Pupillary Distance (PD) is the distance between the centers of your pupils. It determines where you look through the lens of your glasses. It is an essential measurement when buying a new pair of eyeglasses or prescription sunglasses online because it will align the center of each lens of your glasses with the front of your pupil.

There are two types of Pupillary Distance: Monocular and Binocular. If your PD has only one number, that's a Binocular PD. If your PD has two numbers, that's a Monocular PD.

How to measure your PD

The most precise way to obtain your PD is from your eye doctor. If your PD is not included with your prescription, we strongly recommend that you call your doctor and request your PD.

If your eye doctor cannot provide your PD, we can measure it for you in-store. If you can’t have it measured professionally, it is possible to measure it yourself by following the instructions below.

What you will need:

1. Millimeter Ruler (Download our millimeter ruler here ).

2. Mirror or Friend.

Helpful hints:

  • Make sure to measure your PD multiple times to ensure that it is accurate and consistent.

  • For adults the PD ranges from 54mm - 74mm.

  • For children their PD ranges from 43mm - 53mm.

Steps to Measuring your PD on your Own:

1. Stand 8 inches away from the mirror. (Facing the mirror).

2. While facing the mirror, with your face straight, hold the ruler against your brow.

3. Start by closing your right eye, and align the the ruler's zero to the center of your left pupil.

4. While keeping your face straight, close your left eye and open your right eye.

5. Read the mm line that lines up with the center of your right pupil. That number is your Pupillary Distance.

Measuring your PD with a friend:

If a friend or family member is helping you measure your PD, simply stand in front of them with both eyes open, and have them put the zero on the millimeter ruler over the center of one pupil and have then measure the distance to the center of the other pupil.

Things to Remember when Having Your Friend Measure your PD:

  • Have them sit or crouch down while they measure your PD, so that they are out of your field of vision, and you are looking straight ahead.

  • Try to keep your eyes as still as possible. When looking straight ahead, focus on an object that is 10 - 20 ft away above their head.

  • Try your hardest not to look at the person measuring your PD!

Once you’ve measured your PD and have your prescription in hand, ordering your frames online is easy!

Order your glasses online!

To order from Stanton Optical, you will need your up-to-date prescription, pupillary distance (PD), and your credit card.

Select your frames, prescription type, and add-ons, then add the prescription from your account or enter it manually (you will add your PD there if we don’t have it in our records), and check out, as simple as that!

If you were able to get your PD by following the instructions above, you are now all set to make your purchase! Select one of our featured frames below, or click to shop now to see all the frames selections we offer for you online.

FAQs

Where is the PD on my prescription?

Your PD number will be in the ‘PD’ or ‘pupillary distance’ section of your eyeglass prescription. It could also be written where the doctor adds the notes or remarks. If you don’t find any PD information in your prescription, you can try calling your doctor and requesting it.

Why do I need to measure my PD multiple times?

You want your PD to be exact! So, just to make sure and as a good practice, we recommend having it measured more than once. If your lenses aren’t centered correctly, they can cause discomfort and eye strain. A small margin of error might not cause problems, but it’s better to be as accurate as possible.

Is there a range on the PD values?

Normally an Adult PD range goes from 54mm to 74mm meanwhile, the kids PD ranges go from 43 mm to 53 mm, but every person’s PD can vary depending on different factors. Make sure your PD is as much accurate as possible.

I have two PD numbers on my prescription, what does it mean?

If your prescription has two pd numbers, says dual PD, monocular PD, or PD R and PD L; it means that you have a dual PD. It is the distance in millimeters between the centers of each pupil to the bridge of the nose. Normally, the values are the following way: PD 34/31, or PD R 34 L 31, where the first number is the right eye, and the second is the left eye. (Some prescriptions may have ‘OD’ for the ‘right’ eye, and ‘OS’ for ‘left’ eye.)

I don’t have a ruler with me, is there another way to measure my PD?

We recommend using a ruler since it is a tool that most of us can have handy, but if you don't have one, you use our downloadable ruler to measure your PD.Click here to download the digital measurement ruler.

What is a single PD?

The single pupillary distance number is the distance in millimeters between one eye’s pupil to the other eye’s pupil, it is also known as Binocular PD, and it is noted in only one number, i.e. 63 mm, which is different from the dual PD having two numbers, i.e. R 31 mm L 32 mm.

Your PD number will be in the ‘PD’ or ‘pupillary distance’ section of your eyeglass prescription. It could also be written where the doctor adds the notes or remarks. If you don’t find any PD information in your prescription, you can try calling your doctor and requesting it.

You want your PD to be exact! So, just to make sure and as a good practice, we recommend having it measured more than once. If your lenses aren’t centered correctly, they can cause discomfort and eye strain. A small margin of error might not cause problems, but it’s better to be as accurate as possible.

Normally an Adult PD range goes from 54mm to 74mm meanwhile, the kids PD ranges go from 43 mm to 53 mm, but every person’s PD can vary depending on different factors. Make sure your PD is as much accurate as possible.

If your prescription has two pd numbers, says dual PD, monocular PD, or PD R and PD L; it means that you have a dual PD. It is the distance in millimeters between the centers of each pupil to the bridge of the nose. Normally, the values are the following way: PD 34/31, or PD R 34 L 31, where the first number is the right eye, and the second is the left eye. (Some prescriptions may have ‘OD’ for the ‘right’ eye, and ‘OS’ for ‘left’ eye.)

We recommend using a ruler since it is a tool that most of us can have handy, but if you don't have one, you use our downloadable ruler to measure your PD.Click here to download the digital measurement ruler.

The single pupillary distance number is the distance in millimeters between one eye’s pupil to the other eye’s pupil, it is also known as Binocular PD, and it is noted in only one number, i.e. 63 mm, which is different from the dual PD having two numbers, i.e. R 31 mm L 32 mm.