Understanding Pupillary Distance (PD)

This measurement is the basic optical measurement to ensure that the center point of the eyes have been pinpointed and applied to the lenses.

PD is the point where the two pupils meet for any particular distance.

           So for far/distance the convergence point would be at around 20 feet and will be wider than the computer reading distance which is roughly 17" or for reading a book.


 

Mono PD

• Mono PD, this is where the measurement from the center of one pupil to the center of the face is different from the other. That is, the measurements could be Right :33 Left: 29.
• To find the binocular PD you can simply add the two PD  Mono R + Mono L. This is not advisable if you have different Mono PDs in each eye 
• Higher power RX (+-5.00) may need to have mono PD according to some opticians, but it depends on the practitioner.
• Sometimes the PD is written as 33/29.5 this can be combined (62.5) or entered as is.
• If the prescription reads 60/57, then the first number is the distance PD and the second is the reading PD

• As for any changes in the PD measurement up to the age of 20 it will change as the body grows; after that there is no change with age. (Study on PD measurement)

The Average PD Measurement is 60.5 mm 

• 95% of Males measure 55-68mm
• 95% of Females measure 53-65mm
• Kids measure 41-55mm

Above information is for reference only please confirm your particular case with your eye care practitioner.

Here is a ruler you can use - print out with option to size unchecked.
(Right click on the image and choose "open image in new tab" then print)

If you need any help ordering your glasses take a quick look at our glasses guide or give  a call  at 866 217-5878, 9 a.m. – 7 p.m. PT daily or Text 213 769-8009.

 
SHOP FOR YOUR NEW GLASSES NOW