Pupillary distance explained and how to obtain your measurement

     This is the distance glasses between the center of one pupil to the center of the other pupil measured in millimeters. Usually written as one value (60mm) but sometimes written as 34/33 if one eye is slightly further away from the center of the nose than the other.
Unfortunately, many prescriptions do not include a PD measurement or Pupillary distance measurement. Your Optician does not yet HAVE to give you this as part of your eye test and so often chooses not to so as to encourage you to pay over the odds for your reading glasses rather than using our fantastic service at glasses2you. So therefore we encourage you to ask your Optician to supply you with this measurement. However, don't panic if you haven't got this or don't want to ask your optician.
We can still make your Cheap prescription glasses up using an average pupillary distance measurement based on your gender, the size of the frames you have ordered and the experience of our dispensing optician. In the majority of cases this method works extremely well but there will be certain customers gents glasses and women's glasses who through having very strong prescriptions or who significantly differ from the average may encounter some problems. In these cases the specs won't damage your eyes but may well cause some discomfort. If you know that you have a particularly strong prescription or you suspect that you may not fall close enough to what is seen as average sizes we would recommend that you try one of the following methods of obtaining your PD measurement.
Obtaining your own Pupillary Distance Method 1: Ask your partner or friend to help you. Make sure your friend is sat at roughly the same height as you are and ask them to place a ruler across the bridge of your nose upside down so that the millimeter measurements are on the edge of the ruler closest to your eyes. The measurer holds the ruler in their left hand across the bridge of your nose and closes their LEFT eye to avoid any parallax error. With their RIGHT eye open, they then first line up the ruler with the center of your left pupil. Then without moving the ruler they close their RIGHT eye and with their LEFT eye open, read off the measurement to the center of the RIGHT pupil. (See diagram below). Best results are achieved if you fix your gaze on the bridge of the nose of the person taking the measurement. This point should ideally be around 16 inches or 40 cm's away. Method 2: Taking a measurement yourself This is easily measured looking in a mirror and using a ruler! Please follow these steps • Stand in front of a mirror at a distance of about 20cm (8 inches) • Close your right eye • Place your ruler flat against the mirror and align it horizontally with the millimeter scale pointing upwards • Looking over the top of the ruler with your left eye, align the zero mark of the ruler in the center of your left pupil • Now open your right eye and close your left but keep your head still and the ruler in the same position • Read the millimeter measurement corresponding to the center of your right pupil • To be sure, you can repeat this process a few times for consistency Method 3: (With a helper) Please follow these steps: • Put your glasses on • Ask your helper to stand in front of you and mark a dot on your glasses directly above your pupils left and right (Please be sure to use a NON PERMANENT MARKER PEN) • With a ruler, measure the distance between the 2 dots

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