What is my pupil distance?"

Have a friend measure the distance from center of the pupil (black dot) in one eye to the center of the pupil in the other eye. It's like measuring a line connecting the two black dots. This measurement is necessary to ensure the correct positioning of your lenses within the frame you have chosen.
As guideline:
Most adults' PD's are between 55-65.
Most kids' PD's are between 45-55.
To measure your PD:
- Fold this paper so the fold is immediately above the ruler;
- Place the millimeter ruler on the bridge of your nose;
- Have a friend face you about arms length away;
- Have your friend measure the distance between the center of your pupils. (Or you can do it yourself simply by looking in the mirror).