5 easy tips on how to measure pupillary distance

Updated JUN 4, 20234 min read

how to measure pupillary distance
a GlassesUSA.com blog

Buying a new pair of glasses can be a stressful, and at times a complicated task. This is something GlassesUSA.com is committed to resolve. One important area that is worth to be fully aware of is your pupillary distance (PD).

No doubt this is a term you may have heard before, but perhaps were unaware of its meaning. When it comes to finding out more about this subject, you’ll find many ways to measure PD online, but you’ll find that all you need to successfully complete this task is using our handy guide below.

Below we’ll break down the key info you’ll need in relation to PD, as well as a helpful selection of ways on how to measure pupillary distance for glasses from the comfort of your own home.

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What is PD?

So what is PD? Well, PD is simply an abbreviated term for pupillary distance, which effectively refers to the distance between the pupils in each of your eyes. 

PD is traditionally measured in millimeters. This is then used to make sure your lenses are centered. It can also impact on where you will specifically look through in terms of those lenses. This measurement is key when it comes to the details needed to produce prescription lenses.

Securing this information will help you to complete your glasses online order.


Can I Measure my Own Pupillary Distance?

Yes you can, and this is something that individuals are doing more and more. There are many reasons you might look to conduct this measurement yourself, such as the following:

  • To save time
  • To complete an order of online glasses
  • Perhaps because the PD measurement was not listed on your prescription

If you prefer, you can also get your PD checked by an optometrist or at your local optical shop. 

How To Measure Your PD (Pupillary Distance)

Quick Ways to Measure Your PD

If you are worried about how to measure pupillary distance, we got you. Measuring your own PD is a relatively straightforward task, so let’s start with the easiest way to do so. 

STEP 1: Get your pupillary distance ruler (any ruler will do) and make sure you are standing straight in front of a mirror.

STEP 2: Stand approximately eight inches from the mirror.

STEP 3: Position the ruler directly above your eye-line, while standing as straight as possible.

STEP 4: Align the zero on your ruler to the center of one of your pupils, with your other eye shut.

STEP 5: While firmly holding your ruler, open your other eye and measure accurately at what millimeter your second pupil sits. 

STEP 6: Repeat this 4 or 5 times to make sure your measurement is as accurate as possible. 

How to Measure Your PD (Pupillary Distance)

We also recommend you use the GlassesUSA.com prescription scanner app, this is a useful tool  that can help you complete your online prescription glasses order. 

Note that the average pupillary distance for an adult is between 55-75mm, and for a child it can be in the region of 40-53mm.

For another video to accurately measure your Pupillary Distance for glasses at home, checkout Dr. Allens recent video.

Ask a Friend

Though measuring your own PD is fairly easy, you can of course ask the help of a friend, which can make the process even more fail-safe. Simply ask your friend to measure the relative distance between your pupils in the same way outlined above.

In order to record as accurate a reading as possible your friend should assist you in standing completely still, and your vision should not be blocked by them. In other words, look straight ahead without the person who is helping causing an unwanted focus.

What Now?

You should, hopefully, be far less concerned and stressed by what PD means. As well as what the term relates to. Now that you have this key information, how can you use it? 

When you know how to read pupillary distance on your prescription you can now freely shop around our designer glasses and lenses in search of the perfect fit for your face, eyes and stylistic intentions. 

Take a look at our wide range of 1000s of eyeglasses and sunglasses for men, women and kids. Our diverse collection, which is available for all prescription types, includes designer brands such as Oakley, Ray-Ban sunglasses, and many more.

Related Questions

Where can I see my PD on my prescription?

You’ll see this marked as PD in the relevant prescription you are given. This is usually separate from the ‘grid’ section of the script.

Does my PD affect frame size?

No, your pupillary distance measurement won’t affect the size of frames you can wear.

Is there a difference between single PD and dual PD?

Yes. A single PD, is a single number that measures between your two pupils. A ‘Dual’ PD is two numbers, each representing the measurement between one pupil to the center of your nose.


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Published June 27, 2022|Updated June 4, 2023

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GlassesUSA.com

Set out to disrupt the traditional eyewear industry, GlassesUSA.com is the largest online eyewear retailer offering a variety of both high-quality designer and house brands with a wide-range of styles and lens types including: single vision lenses, multifocal lenses, Rx sunglasses, sports glasses, kids glasses, contact lenses, digital protection, anti-reflective coatings and more.