The pupillary distance (PD) measurement is a requirement for people who want to purchase eyeglasses. Here, find out how to measure your PD using a mirror and a ruler. Share on Pinterest Some eyewear ...

Pupillary distance helps center your eyeglasses prescription. Your eyeglasses provider normally measures it for you, but you won’t find it on your prescription. If you order glasses online, you’ll ...

This option is useful for those who may travel to another country and need to measure something such as clothing in a department store. For more help getting the most out of your Apple devices, check ...