We recommend using a soft tape measure. If you do not have a soft tape measureyou can use something like string, wrap it around the fetlock, mark where the end meets the rest of the string and then simply lay it flat next to a tape measure,toget your measurement.
Be sure to measure boththe FRONT & BACK fetlocks as they are often differentsizes. It is ok to order bootsin one size for Front and adifferent size for the Back
Small: 8.5 - 9.5 in. / 21.59 - 24.13 centimeters
Medium: 9.5 - 10.5 in. / 24.13 - 26.67 centimeters
Large: 10.5 - 11.5 in. / 26.67 - 29.21 centimeters
XL: 11.5 - 12.5 in. / 29.21 - 31.75 centimeters
XXL: 12.5 - 13.5 in. / 31.75 - 34.29 centimeters