You can find your QardioBase serial number on:
1) The middle of the inside of the battery compartment, which you can access by removing the battery hatch on the back of the scale, as shown here:
2) On the back of your QardioBase box, at the bottom right as shown in the photo here:
QardioBase is the wireless smart scale and body analyzer that combines intelligent features, ease of use, and sleek design to make weight and health management an integral part of your everyday life. Learn more about QardioBase smart scale here.