We offer three sizes for adults and three sizes for children. To find your best size, measure the diameter of the widest part of your hand, not your wrist. If you are in between sizes, size down if you want a tighter fit on your wrist, or size up if you want a looser fit on your wrist. The inner circumference of each adult bangle are: Small – 7 inches / 17.78 cms Medium – 7.5 inches / 19.05 cms Large – 8 inches / 20.32 cms Extra Large – 8.5 inches / 21.59 cms The inner circumference of each baby bangle are: Small (ages 1-4) – 5.3 inches / 13.5 cms Medium (ages 3-7) – 5.7 inches / 14.5 cms Large (ages 6-10) – 6.4 inches / 16.3 cms