If you are interested in upgrading your watchband or if you just need a replacement, you must determine what size of watchband correctly fits your watch and wrist. There are two elements to measuring a watchband. First, you must measure the watchband strap size, which determines how wide the band is. Secondly, you must measure the watchband strap length. Once you have these measurements, you can confidently purchase a new band that will fit your watch correctly and wear comfortably on your wrist.
Measure Strap Size
Lay the watch face up, on a flat surface. Note that the watchband can be connected or detached.
Measure the distance between the two lugs on the top or bottom of the watch with a metric ruler. The lugs are the two protruding arms that the watchband connects to on the top or bottom of the watch. Be sure to measure from the inside of each lug. Alternatively you can measure the distance between the two lugs using a caliper (calipers are more accurate than rulers).
Record the measurement in millimeters. For example, if you measured 23 millimeters, that is your watch strap size.
Measure Strap Length
Remove the watchband from your watch, if not already detached.
Lay both halves of the strap on a flat surface so that the ends of the watchband that normally connect to the watch lugs touch but do not overlap.
Measure the length of the entire watchband using an English ruler, excluding the buckle.
Record the measurement in inches. For example, if you measured 7 1/4 inches, that is your watch strap length.
Lay the watchband on top of the English ruler to make it easier to accurately measure the length of the watchband. Look for the watchband strap size on the back of the band; sometimes manufacturers print this information on the watchband.