How to measure your Pupillary Distance (PD)

Straight off the cuff you’re probably thinking, what on earth is my Pupillary Distance? Or perhaps you’re a self-proclaimed optical expert and you know exactly what we’re talking about. If so, why not head straight to our new arrivals page and take a look at our new range of glasses for men and women

But if you’re still a little perplexed by what we’re talking about then stick around, it might open your eyes to some spectacular knowledge. 

What is Pupillary Distance (PD)?

Pupillary Distance or PD is the distance measured between the eyes, measured from the centre of each pupil. This is an important measurement when choosing your new frames to ensure the optimum point of vision in the lens is directly in front of your eye

How do you measure Pupillary Distance online? 

It’s really important to make sure PD is measured correctly, it is therefore possible to have it measured for you at your local opticians but if you feel confident enough, it is also straightforward to do it at home. You will need this measurement if you are ordering glasses online.

Steps to measure your PD safely at home:

  1. Stand about arm’s length (30cm) away from a mirror
  2. Hold a ruler up against your eyebrows
  3. Close your right eye, then line up the ruler so that 0mm is in line with the middle of your left pupil
  4. Look straight ahead again and then open your right eye and close your left
  5. Your PD measurement will be the figure that lines up with the centre of your right pupil

How do I measure my PD without a ruler?

At Arlo Wolf, we can measure your PD for you! Simply follow the steps below to take a selfie and our team can calculate your pupillary distance. You’ll just need your phone and a card with a magnetic stripe.

Step 1: Remove your glasses.
Step 2: Hold any card with a magnetic stripe under your nose with the magnetic stripe facing outwards.
Step 3: Take a selfie at arm’s length.


There are also various mobile apps that can calculate your PD using your phone’s camera, such as EyeMeasure and GlassesOn.

Why is it important to get your PD measurement correct?

Put simply, it allows the optimum point of vision in the lens to be put directly in front of your eye. For those with strong prescriptions, your PD becomes even more important. If we need your measurement, one of our team will be in touch. 

If you are not feeling confident about measuring your PD, you can also send us a pair of your old glasses to take your PD measurement from. Your pupil distance does not change and will always remain the same, so they don’t even have to be a recent pair of glasses, or match your existing prescription.

Does pupillary distance have to be exact?

The pupillary distance measurement does not have to be 100% precise to be applicable, as it can tolerate a small error range. A PD difference of 1mm is not going to cause too much discomfort, and would not be noticeable. If you do measure your PD at home, it is recommended that you try several attempts to be sure you get an accurate measurement.

Finding the right frames for you

Another important factor when choosing your next frames is whether they suit your face shape. Luckily, at Arlo Wolf, we have put together a useful face shapes guide so you can match the right frames with your face! Not ready to swap out your current frames? No worries, we also offer a reglazing service for when your prescription changes before your fashion – check it out here.

When ordering your new glasses with Arlo Wolf, we offer a try before you buy service so you can try on your desired frames at home fashioned against your wardrobe. Choose up to four frames, and we’ll send you the samples for you to check out – then you return them in our pre-paid postage package. Ordering glasses online never felt so streamlined!