Watch band widths are measured in millimeters. Most leather watch bands are marked with the size. As shown in the image below. If your band has this number that is the width of the band you need for your watch. If your band does not have this number then to determine the width of the watch band, you will need to measure the distance between the lugs (Lugs are where your band attaches to your watch). As shown below. You can use a ruler with either inches or millimeters to measure. If you are using inches it will need to be converted to millimeters. Note: When measuring please measure the watch between the lugs. Not the band. Watch bands can shrink or a wrong size could have been installed the last time. The chart below will help you convert inches to millimeters. Inches Millimeters Distance between lugs in inches: Millimeter (mm) size: 1 11/64" 30mm 1 7/64" 28mm 1" 26mm 15/16" 24mm 7/8" 22mm 13/16" 21mm 25/32" 20mm 3/4" 19mm 11/16" 18mm 21/32" 17mm 5/8" 16mm 19/32" 15mm 9/16" 14mm 1/2" 13mm 15/32" 12mm 7/16" 11mm 3/8" 10mm 11/32" 9mm 5/16" 8mm 15/64" 6mm		The length of watch bands are measured in inches. To determine the length of the watch band you need, measure the leather portion of your band. Note: Do not include the buckle in your measurement. The tables below are approximate lengths for the bands from each manufacturer. Banda Watch Band Lengths Gent's Regular 7.48 inches Gent's Long 8.07 inches Gent's XL 8.66 inches Gent's Short 6.89 inches Ladies Regular 6.89 inches Ladies Long 7.47 inches Ladies Short 6.30 inches   deBeer Watch Band Lengths Gent's Regular 7.5 inches Gent's Long 8.25 - 8.5 inches Gent's XL 9.5 inches Gent's Short 6.75 inches Gent's Open End 7.5 - 8.5 inches Ladies Regular 6.75 inches Ladies Long 7.75 - 8.5 inches Ladies Short 6.0 - 6.75 inches Ladies Open End 6.5 - 8.5 inches   Hadley Roma Band Lengths Gent's Regular 7.5 inches Gent's Long 8.375 inches Gent's XL 9.0 inches Gent's Short 6.625 inches Ladies Regular 6.5 inches Ladies Long 7.375 inches Ladies Short 6.25 inches   WBHQ Watch Band Lengths Gent's Regular 7.56 inches Gent's Long 8.0 inches Gent's XL 9.0 inches Gent's Short 7.125 inches Ladies Regular 6.5 inches Ladies Long 7.375 inches Ladies Short 6.25 inches Note: The length you measure is apporximately the size you need. For instance if you measure 7.4" you will need a band that is around that length so a 7.5" to 7.7" band will work.