You'll need to know your PD if you want to order  new glasses online  from VIVUE. Don't worry if your glasses prescription doesn't include your PD, we can show you how to measure it by yourself at home. It’s easy to measure PD online — all you need is a mirror and our printable ruler, available to download below. You can also measure friends’ sizes and have them assist with telling you yours. If you’ve ordered prescription eyewear online with us before, you may have asked yourself, “what’s my PD and how do I measure it?” You can usually find your pupillary distance, also known as interpupillary distance, on your prescription, but if it’s missing, we can help!

Pupillary distance, or PD, refers to the distance in millimeters between the center of one pupil to the center of the other. Having a correct PD on your vision prescription ensures that you’re looking through the ideal spot in your lenses.

If this number wasn’t provided on your prescription by an eye care professional, you can measure it yourself at home. Download and print our  PD ruler, then follow the simple steps to measure your pupillary distance.

Measuring your pupillary distance is fairly simple, even if you're alone. All you need is our PD ruler and a mirror. Once you have what you need, follow the steps below:

You may want to relax, then remeasure a few times so you get the most accurate number. If you get different numbers each time, use the average as your final measurement. For example, if you measured your PD five times, add together all five of the numbers you got. Once you have that number, divide it by five. This will give you your final, or average, PD.

If you need progressive or bifocal lenses, you’ll also need to measure your near focus PD. You will need someone else to measure this for you to get the most accurate reading.

The person measuring should follow the same instructions as they would to get your regular PD. However, instead of focusing on an object 10 to 20 feet away, hold a pen between you and the measurer and focus on it. While you do this, the measurer can read and mark down your PD.

Your interpupillary distance is important for ensuring a particular point of the lenses goes directly over your pupils. This is especially true for people with high-powered lenses.

Your interpupillary distance may or may not be included on your vision prescription. However, it's normally listed as one number — 64 for example. If there’s a difference in measurement between the bridge of your nose and the center of each eye, your PD may also appear as two numbers — like 32 and 31. This is your PD separated for each eye.