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How to Measure and Understand Pupillary Distance (PD) at Home | Single vs Dual, Kids, & Missing PD
To make sure your custom lenses line up perfectly with your eyes, our laboratory needs a measurement called Pupillary Distance (PD).
What is Pupillary Distance (PD) and why is it important?
Pupillary Distance is the exact distance, measured in millimeters, between the centers of your pupils.
When our optical laboratory cuts your lenses to fit your chosen frame, they use your PD to position the "optical center" (the clearest part of the lens) right in front of your pupils. If your PD measurement is incorrect or missing, you may experience eye strain, headaches, or slight visual distortion when wearing your new glasses.
How do I find PD on my prescription sheet?
Before you assume your PD is missing, let’s make sure it isn’t just hiding! Doctors write it down in a few strange ways. Check your paperwork for these common tricks:
Look for Abbreviations: It is almost never spelled out. Look for labels like PD, P.D., or Dist. PD.
Check the "Notes" Box: Doctors frequently leave the main grid blank and scribble the PD down in the Notes, Comments, or Remarks section at the very bottom of the page.
Look for Two Numbers: If you don't see a single number like 62, look for two smaller numbers separated by a slash (like 31/31 or 31.5/32.5). That is just a Dual PD, and it works perfectly!
Single PD vs. Dual PD: How do I enter them on the website?
When checking out, click Choose Lenses on your favorite frame and answer the prompt, "What do you use your glasses for?". Once you select Fill it out online, look for the PD section at the bottom of the form. Here is how to input your values:
Single PD (Binocular PD): This is one single number (e.g., 62).
👉 How to enter it: Just tap or click the menu next to PD and pick your number.
Dual PD (Monocular PD): This is two separate numbers (e.g., 31.5 / 32.5). The right eye is always listed first.
👉 How to enter it: Check the box right below it that says "I have 2 PD numbers". Two new boxes will pop up so you can easily pick a number for your right eye and your left eye.
🛑 Can't find your exact PD number in the dropdown menu?
If your prescription has a specific PD number that isn't appearing in our standard selection menus, do not worry! You can still complete your order perfectly.
The Comment Box Hack: Simply leave the dropdown menu as it is. Scroll down to the Comments / Notes section at the bottom of the lens configuration form.
Type it in manually: Type your exact PD number directly into that comment box (e.g., "My exact PD is 55.5").
This text box is always available whether you are typing your prescription values manually or simply uploading a photo of your paperwork. Our optical laboratory technicians read every single comment manually before cutting any lenses, so they will ensure your custom frames are crafted perfectly to your exact number!
What if I don't know my PD or leave it blank?
For Adult Orders: Use Our "Safe Bet" Defaults
If you are an adult, don't know your PD, and cannot measure it, you can still confidently place your order! Our dropdown menus are automatically pre-set to safe, industry-standard adult averages:
Distance PD (Single Vision): Leave this set to the default of 62.
Near PD (Progressives / Bifocals): If your prescription does not list a specific Near PD, leave this field set to the default of 59 (our laboratory automatically calculates this close-up reading zone by subtracting 3mm from the standard 62mm distance average).
Why this works: 62mm is the standard global average for adults. It works comfortably for the vast majority of adult wearers!
For Children's Orders: Strict PD Requirement
While we are excited to produce your child's glasses, we are unable to do so without their specific PD measurement.
Because children have smaller faces, never use our adult defaults (62 or 59) for a child's order. Doing so will cause severe eye strain and visual discomfort.
How to get your child's PD: If it is missing from their prescription sheet, the easiest and safest route is to call your eye doctor’s office. They always keep your child's PD on file in their medical records and will gladly read it to you over the phone!
Our Policy: Because kids need an exact, safe fit, we must have an accurate, child-specific measurement before we can begin manufacturing.
Standard PD Averages (To Double-Check Your Numbers)
If you want to double-check your numbers to ensure they look right before completing your order, use these standard baselines:
Adult PD Range: Typically ranges between 54mm and 74mm (62mm is our default).
Adult Dual PD: Typically looks like 31/31 or 32/32.
Children's PD Range: Typically ranges between 43mm and 54mm.
How to measure your PD at home (The Mirror Method)
If you need to measure your own PD right now, all you need is a standard ruler that shows millimeters (mm) and a mirror.
Stand straight and face a mirror in a well-lit room, about 8 inches away. Hold the ruler flat against your eyebrow line and keep your face straight.
Close your right eye and line up the 0mm mark of the ruler exactly with the center of your left pupil.
Looking straight ahead, open your right eye and close your left eye.
Look into the mirror and note the exact millimeter mark that aligns with the center of your right pupil.
Repeat this process 2 or 3 times to ensure you are getting a consistent, accurate reading!
What is 'Near PD' (NPD) and do I need it?
Near PD is a specific measurement used only if you are ordering progressive lenses or lined bifocals. Your pupils naturally turn slightly inward toward your nose when you look down at a close-up object like a book or a phone.
If your doctor did not write a separate Near PD on your paperwork, don't worry at all:
Automatic Laboratory Adjustment: If your prescription does not list a specific Near PD, leave this field set to the default of 59. (See the Near PD section at the bottom of this page to see how our lab automatically calculates this for you!)