*Shoe sizes are for standard U.S. shoes
Measuring Your Arch Circumference
Your arch circumference is the length from a point on top of your foot, down around your foot and over the highest point in your foot arch, and back to the same point on the top of your foot.
To measure your arch circumference, place your bare foot on the ground and wrap a measuring tape around your foot. Make sure that the measuring tape crosses over the highest point of the arch beneath your foot, and that the measuring tape wraps around your foot in a straight line at all points.