Pupillary Distance (PD) or interpupillary distance (IPD) is the distance in millimeters from the center of one pupil to the center of the other pupil. This measurement is needed to ensure that the lenses are correctly centered within the frames of your kid's glasses. The industry standard allows for 2-3mm of wiggle room for the measurement without negatively impacting your child's vision.
Often times, the prescription will include this measurement! If it does not, we always recommend checking with the eye doctor to see if they have this measurement on file. If they do not, you can measure their PD right at home. For reference, most kids have a PD between 42-65mm.
If you're hesitant about measuring, download our mobile app to scan your child's facial measurements (see links below) or you can text a picture of the measurement tool next to your child's eyes to (616) 202-5844 and we can confirm their PD!