How to Measure Pupillary Distance at Home for Glasses
Are you about to purchase your eyeglasses online, but you have reached the point of entering your PD? But not sure about the distance between pupils for eyeglasses.
Don’t worry — you’re not alone. Most individuals are not even aware of what is meant by Pupillary Distance (PD), let alone measure the PD. But the thing is this: a minor mistake in this tiny measurement can hurt eyesight and eyes as well as cause headaches.
In this complete guide, I’ll teach you how to measure the distance between your pupils gradually using a ruler, cell phone programs, your old spectacles, or even professional equipment.
What is Pupillary Distance (PD)?
Pupillary Distance Field (PD) refers to the distance that the centers of your pupils are placed in, which may vary according to the number of millimeters (mm). It is a small yet very essential measurement that puts your prescription glasses right in line with your eyes.
Your lenses ought to be aligned with your eyes’ pupils. Otherwise, it may cause blurred vision, eyestrain, or even a headache.
Why is PD Important?
- Gives proper lens guide orientation
- Lessens the stress and pain on the eyes
- Prevents visual distortion
- Vital for progressive or multifocal lenses
- They will be required to place online glasses orders
Types of Pupillary Distance Measurements
The type of PD measurements you need to be aware of is twofold:
1. Binocular PD
This is the overall length between the center of the same pupil to the other. As an example, your PD may be 62mm, which is 31mm per eye in the split.
This is the general form of PD measurement, which is most of them are written in a single number form.
2. Monocular PD
Monocular PD is the measurement, in terms of centimeters or inches, between the center of your nose, on the one hand, and the pupils, respectively, on the other hand. This would be particularly helpful in case you do not have symmetrical features on your face.
It’s usually written like this:
- Left: 30.5mm | Right: 31.5mm
Monocular PD is ideal for:
- People with asymmetrical facial structures
- High precision optical glasses
- High-accuracy lenses
- Multifocal and progressive lenses
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Method 1: Using a Millimeter Ruler
What You Need
- A millimeter ruler
- A mirror or a friend to help you
- A steady hand
How to Do It
- Hold a mirror approximately 8 inches (20cm) away.
- To your brow hold the ruler.
- Close one of your eyes (the right one) and match the 0mm mark with the middle of your left pupil.
- Open the right eye and close the left, and with the ruler still where it is.
- Use the millimeter line that corresponds to the center of your right pupil.
Tips
- Do these two to three times to ensure the correctness.
- Write it down immediately!
Method 2: Using a PD Measurement App
Specific apps are even available specifically for this, and they will work well too.
What You Need
- A smartphone
- Good lighting
- A standard-size card (credit card, ID, etc.) for scale
How to Do It
- Install a trustworthy PD measuring app, of which there are GlassesOn or EyeMeasure.
- Follow the instructions (in most cases, you take a selfie with the card on your forehead or under your nose).
- The app takes advantage of the known width of the card and scales your PD.
Benefits
- Fast and easy
- Single vision glasses are good in accuracy
- Can measure monocular PD as well
Method 3: Using Your Old Glasses
In case you are already wearing glasses, which perfectly fit you.
What You Need
- Your old pair of glasses
- A marker or dry-erase pen
- A mirror
- Ruler (millimeter scale)
How to Do It
- Go and wear your old spectacles, then come near the mirror.
- Open both eyes and cross the center of each pupil on the lenses with the pen.
- Remove the glasses to measure the distance between the two dots.
That’s your Binocular PD.
Why This Works
- It rests on actual pupil orientation in an already-fitted frame
- It can be pretty accurate if done carefully
Method 4: Get It Professionally Measured
If you want to be 100 percent certain, then having a professional measurement of PD is the most secure course.
Where to Get It
- Clinic of an optometrist (in some cases, eye exams are involved)
- Optical stores and lens stores
- There are online shops that provide remote PD services
What to Expect
- Takes 1-2 minutes
- The connection is put into use by the use of a pupillometer or digital scanner
- Gives you both monocular and binocular PD
Common Questions You Might Have
What’s the Average PD?
For adults:
- The average is between 60mm to 66mm
- Men: Usually around 64mm
- Women: Usually around 62mm
The average PD of children is 41mm to 55mm.
Can I Estimate My PD?
Yes, but I would not use the estimated PD in my complex prescriptions or progressive lenses. In the case of single-vision lenses, an approximate PD will be a temporary solution, but it is always advisable to have an exact PD.
Is PD the Same for Everyone?
Not at all. Each individual possesses a differently structured face. Your PD can even be different in the left and right eyes. That is why you should not copy the PD of another person.
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Final Words from Me
It may sound like a small thing to measure your pupillary distance, but believe me, it can make all the difference in how you use your eyeglasses. You can do it at home with a ruler, on an application, or go to a professional, but make sure that you do not skip it.
But now you don’t have to — you’re equipped with all the tools, methods, and knowledge to measure your PD like a pro.
