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MAKE THE MOST OF YOUR FSA BENEFITS BEFORE 12/31

How to measure pupillary distance (PD)

What is PD?
Your Pupillary Distance, or PD, is the distance in millimeters (mm) between the center of one pupil to the center of the other. A personalized fit starts with measuring your pupillary distance: it indicates which part of the lens you look through, ensuring optimal comfort and clarity.

Why is it important?
If your PD isn’t right, it can cause eye strain, fatigue, or simply not being able to see properly. The higher your prescription, the bigger the effect an incorrect PD can have. So get measuring!

How to measure pupillary distance (PD)-What is PD? Your Pupillary Distance, or PD, is the distance in millimeters (mm) between the center of one pupil to the center of the other. A personalized fit starts with measuring your pupillary distance: it indicates which part of the lens you look through, ensuring optimal comfort and clarity. Why is it important? If your PD isn’t right, it can cause eye strain, fatigue, or simply not being able to see properly. The higher your prescription, the bigger the effect an incorrect PD can have. So get measuring!
single pd-SINGLE PD is the pupillary distance between the center of one pupil to the other, which can be a distance PD or near PD. Distance PD can be used to order any type of prescription glasses except reading glasses. Read below to learn how to calculate near PD for reading glasses.

single pd

SINGLE PD is the pupillary distance between the center of one pupil to the other, which can be a distance PD or near PD. Distance PD can be used to order any type of prescription glasses except reading glasses. Read below to learn how to calculate near PD for reading glasses.

dual pd-DUAL PD, or monocular PD, consists of two numbers and is the distance between the centers of each pupil to the bridge of the nose. Dual PD is usually written in the following notation: 32/30. The first number is always the right eye (OD) measurement, and the second number is the left eye (OS).

dual pd

DUAL PD, or monocular PD, consists of two numbers and is the distance between the centers of each pupil to the bridge of the nose. Dual PD is usually written in the following notation: 32/30. The first number is always the right eye (OD) measurement, and the second number is the left eye (OS).

 
With the Opthy app By yourself With the help of a friend
Ophty LP Image eyeglasses

1.POSITION YOURSELF

Put on glasses and keep your felt tip marker handy. Focus on an object at least 20 feet away.

Smart tip: If measuring for near-sighted glasses, focus on a close object like reading material or a computer screen.

2. MARK YOUR GLASSES

Mark with your felty marker on your right lens directly over the object. Mark over the object on your left lens.

With both eyes, make sure the markings overlap into a single dot.

3. MEASURE

Measure the distance between the two dots with a millimeter ruler. That number is your PD. Jot it down.

Smart tip: The average range of an adult PD is 54-74 mm, the average range of a child PD: 43-58 mm

Ophty LP Image eyeglasses

1.POSITION YOURSELF

Focus on an object 20 feet away.

Smart tip: If measuring for near-sighted glasses, focus on a close object like reading material or a computer screen.

2.USE THE RULER

Stand about 8” away from a well-lit mirror.

Look straight ahead into the mirror and position the ruler over the bridge of your nose.

3.MEASURE

Starting with the right eye, line up the zero end of the ruler at your pupil; measure the distance from your right to your left pupil. The millimeter number that lines up with your left pupil is the measurement you want: that number is your PD!

Smart tip: Just to be sure, measure a few more times to make sure you get the same number. You want it to be accurate. The average range of an adult PD is 54-74 mm, the average range of a child PD: 43-58 mm