How to Measure Pupillary Distance (PD)
Your Pupillary Distance (PD) is an important measurement you’ll need when ordering prescription glasses online. If your eye doctor didn’t include it on your prescription, don’t worry — you can measure it yourself at home with a mirror and a simple ruler.
What Is Pupillary Distance?
Pupillary Distance (PD) is the distance, in millimeters, between the center of one pupil and the center of the other.
A correct PD makes sure your eyes align with the optical center of your lenses, giving you the sharpest and most comfortable vision.
If your prescription doesn’t list your PD, you can measure it easily at home.
How to Measure Your PD at Home
You’ll need:
• A mirror
• A ruler marked in millimeters (MM)
• Good lighting
Steps:
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Stand about 8–12 inches away from a mirror.
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Hold the ruler against your brow line.
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Close your right eye and align the zero mark of the ruler directly above the center of your left pupil.
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Without moving the ruler, open your right eye and close your left eye.
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Look straight ahead and read the number directly above the center of your right pupil.
This number is your PD.
Tip:
You can also ask a friend or family member to measure your PD for better accuracy.
Types of PD
Single PD:
One number (example: 63mm). Most adults use single PD.
Dual PD:
Two numbers (example: 31mm / 32mm). Used for more precise fitting, especially in progressives or multifocals.
• First number: distance from center of nose to left pupil
• Second: distance from center of nose to right pupil
Why PD Matters When Ordering Glasses
Matching your PD with your prescription ensures your lenses are made correctly.
If the PD is off, your glasses may feel uncomfortable, cause eye strain, or not provide clear vision.
Get the Perfect Fit with Mafami
Once you have your PD and prescription ready, browse Mafami’s collection of handcrafted eyeglasses and sunglasses made for comfort, clarity, and everyday style.