### How to Measure Your PD with A Regular Ruler

Pupillary distance (PD) is the measurement of the distance from the center of one pupil to the other, which is necessary while ordering prescription eyeglasses or sunglasses online. A correct PD ensures that the lenses optical center is lined up with your pupil to achieve vision clarity. If you cannot get it from your original prescription script, it’s quite easy for to you get it on your own at home.

Two ways to get your Pupillary distance

1）Pupillary distance is the measurement of the distance from the center of one pupil to the other.

Step 1

Find a ruler that measures in millimeters(mm).

Step 2

Stand 8-10 inches away from a mirror, looking straight ahead with a ruler against your brow and line up the zero on the ruler with the center of the pupil.

Step 3

Without moving your head, swap eyes and read off the scale where the center of the pupil falls in mm(millimeters).

Step 4

Repeat step 1-3 several times to ensure your technique is accurate and get the correct PD measurement.

2） Given if your eyes aren’t perfectly symmetrical, you can measure the distance from the center of your nose (bridge) to the center of pupil to get your dual pupillary distance. In instances like this, a dual PD measurement will typically result in a better fitting lens due to each eye having its exact pupillary distance. In this way, the lens optical center is correctly positioned for each eye.

Step 1

Find a ruler that measures in millimeters(mm).

Step 2

Stand 8-10 inches away from a mirror, looking straight ahead with a ruler against your brow and line up the zero on the ruler with the center of your nose bridge. Please make sure that the ruler is lined up perfectly with the center of your left pupil, in this way to get your left PD measurement.

Step 3

Without moving your head, get the zero on the ruler now centered with your nose bridge, make sure the ruler is line up perfectly with the center of your right pupil, in this way to get your right PD measurement.

Step 4

Repeat step 1-3 several times to ensure your technique is accurate and get the correct dual PD measurement.

The PD can be written in below two ways.

1. PD (OU), written as “56” for example, means the binocular PD which is the distance between your right pupil and your left pupil. Most adults PD binocular PD falls somewhere between 52-75mm. However, for some men’s PD could be on the higher side of this span (56-75) mm, while most women’s PD will fall somewhere between 52-64mm. The average PD distance for men is approximately 64mm while the average PD for women is right around 62mm.

PD(OU) can be label as Far or Near. For example, 63/60. Far PD 63 is for general use like driving. 60 is for seeing intermediate distance or reading. The difference between Far PD and Near PD is around 2-3mm.

2. Dual PD

Dual PD consists of two numbers and is the distance from each pupil to the center of nose bridge. Dual PD is written as two numbers, for example, 31/30, the former one is the PD 31 for the right eye and the later one 30 is the PD for the left eye. Dual PD can be for general use like driving or for seeing nearby like reading as well.

#### How to Fill the PD When Ordering

1. If you have one PD number like “63”, please select 63 when taping in your prescription. If your PD is written as "63/60," then "63" is your far PD and "60" is your near PD. Please enter your "Far PD" for distance vision eyeglasses and enter your "Near PD" for reading glasses.

2. Given if your PD on the prescription script is written as Dual PD, such as 32/31, please check Dual PD. Tap 32 for the right eye and 31 for the left eye.