how to measure pupillary distance pd

How To Measure Pupillary Distance (PD)

What Is Pupillary Distance (PD)?

A personalized fit starts with measuring your pupillary distance – that’s the space between the centres of each of your pupils. The pupillary distance is measured in millimetres and tells the lens maker where to put the optical centre on each lens. Note that if your ruler is in centimeters, you can convert it online to millimetres, but don’t measure your PD in inches. It might result in a wrong conversion and your measurement won’t be accurate. If you measure your PD the wrong way, you won’t have the right lens placement.
You can ask your eye doctor to include your PD measurement on your prescription, or if you don’t have it, here’s how you can measure it yourself.

STEP ONE

Put on glasses. Have a felt tip marker handy!

STEP TWO

Focus on an object at least 20 feet away.

STEP THREE

Mark on your right lens directly over the object.

STEP FOUR

Mark over the object on your left lens.

STEP FIVE

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

STEP SIX

Measure the distance between the two dots with a millimeter ruler.

NOTE:

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

No Glasses Handy

Don’t have a pair of glasses handy? You can still measure your pupillary distance using a mirror, a small ruler marked in millimetres, a pencil &  paper.

STEP ONE

Stand about 8″ away from a well-lit mirror. Grab your small ruler in one hand. Have your pencil and paper handy. Look straight ahead into the mirror and position the ruler over the bridge of your nose.

STEP TWO

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 pupillary distance (PD). Jot it down. Just to be sure, measure a few more times to make sure you get the same number. You want it to be accurate.

Getting A Friend To Help

WHAT YOU NEED?

A friend, a small ruler marked in millimetres, a pencil & paper.

STEP ONE

Face your friend and look straight ahead with both eyes open.

STEP TWO

Have your friend hold the ruler up to your right so the zero end lines up with your pupil. Measure the distance from your right to your left pupil. The number that lines up with your left pupil is your pupillary distance (PD). Jot it down. Try it a couple times to make sure your measurement is accurate.

STEP THREE

Have your friend repeat the process on your left eye by measuring the distance from your left pupil to your right. Use the number that lines up with your right pupil. That’s your pupillary distance (PD). Jot it down. Do a couple tries to make sure the pupillary distance (PD) measurement is right.

Once you’ve got your pupillary distance (PD) measurement, fill in the numbers in your cart and you’re good to go.

Contact us, if you need help or have questions.

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