This tool shows which size watch strap is needed and really comes in handy when ordering new watch straps online. Just find the slot that fits between the lugs of your watch and the size (in mm) is listed! I included the most common watch band sizes: 12, 14, 15, 16, 17, 18, 19, 20, and 22 mm.

The watch strap sizer also allows you to visualize the thickness of the watch strap. Again, the most common strap thicknesses are included: 2.0, 2.5, 3.0, 3.5, and 4.0 mm.

The back of the Watch Strap Sizer features the name of my blog, Grail-Watch.com but I also included a "no logo" version if you don't want to print that.