What Is PD? Measure Pupillary Distance for Glasses

One tiny number. Much better lens placement.

PD isn’t usually on your glasses. Here’s where to find it.

Pupillary distance, or PD, is the distance between the centers of your pupils, measured in millimeters. It’s a fitting measurement, not the lens prescription itself. It may appear on your prescription, or your eye doctor may keep it separately in your record.

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Check your prescription

Look for PD, pupillary distance, distance PD, or two numbers marked right and left. It may sit near the prescription details or in a separate fitting section.

Ask your eye doctor

Your optometrist or optician may already have your PD on file, even if it wasn’t printed on the prescription. Ask for the measurement in millimeters.

Don’t hunt for it on the glasses

PD isn’t normally engraved or printed on your glasses. An old order receipt or eyewear account may list it, but the glasses themselves usually won’t.

Single PD vs. dual PD

Single PD

One number measures the total distance from the center of one pupil to the center of the other. It may look like 63 mm.

Dual PD

Two numbers measure from the center of your nose to each pupil. It may look like 31/32 mm or be labeled right and left.

Keep the format your doctor gave you. If an order asks for one distance PD and you have two distance-PD numbers, add them together. If it asks for dual PD and you only have one number, don’t automatically split it in half. Faces aren’t perfectly symmetrical, because women are people, not geometry homework. Ask us or your eye doctor.

How to measure PD at home with a mirror

A professional measurement is the most accurate. If you need a careful home check, use a rigid millimeter ruler, a mirror, and bright, even light. Inches are not invited to this particular party.

Set up straight

Stand about 8 inches from a mirror. Keep your head level and look straight ahead.

Place the ruler

Hold the ruler flat and horizontal against your browline. Keep it steady while you switch eyes.

Line up the zero

Close your right eye. With your left eye open, line up the ruler’s zero mark with the center of your left pupil.

Read the other pupil

Without moving the ruler, close your left eye and open your right. Read the millimeter mark that crosses the center of your right pupil. That number is your single PD.

Repeat it three times

Start over and measure at least three times. Use a number only when the readings agree. If they keep changing, don’t guess.

Let a friend measure it

Sit or stand with your head level and look at a fixed object across the room, not at the person measuring you. Your friend should hold a millimeter ruler straight across your browline, align zero with the center of one pupil, and read the center of the other. Repeat the measurement three times.

Average isn’t a measurement. Don’t borrow a stranger’s PD from the internet, guess from an old pair, or choose a number because it looks normal. Your lenses need your eyes, not somebody else’s face math.

When not to guess

Ask your eye doctor, optician, or LadyBoss for help when:

Your repeated measurements don’t agree within 1 mm.
You were given both near PD and distance PD and aren’t sure which one the order needs.
Your prescription includes prism, progressive lenses, or other fitting instructions.
You can’t keep the ruler level or clearly identify the center of each pupil.
Your doctor supplied dual PD and the numbers don’t match what you measured at home.

What is pupillary distance?

Pupillary distance is the distance between the centers of your pupils, measured in millimeters. It helps place prescription lens power in front of your eyes.

Is PD on my glasses or my prescription?

PD may be listed on your prescription, but it usually isn’t printed on the glasses themselves. If it isn’t listed, ask your eye doctor, check a previous eyewear order, or measure it carefully.

Is PD part of my prescription?

PD is a fitting measurement used to position your lenses. Some offices print it on the prescription and others keep it separately in the patient record.

What is the difference between near PD and distance PD?

Distance PD is used when your eyes focus farther away. Near PD is slightly smaller because your eyes turn inward while reading. Use the measurement requested for your lens type, and ask before choosing if you were given both.

What if I don’t have my PD yet?

Ask your eye doctor or optician for the measurement first. If you still aren’t sure which number your order needs, contact LadyBoss before choosing one.

Your eyes. Your number.

Now put that PD to work.

Shop prescription glasses made exclusively for women, or ask us for help before you order. Tiny measurement handled. Queen behavior restored.

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