You can use a measuring tape to measure your wrist. Wrap the tape measure around the wrist on which you plan to wear your ZENGER bracelet. Make a note of the number at the point where the tape meets the 0. To ensure the bracelet fits comfortably, add 0.50 inch. You can then add or subtract according to whether you prefer a loose, exact or tight fit. Below is a picture on how to measure your wrist.