If you are unsure of your size, make a fist, and measure with a flat ruler from the middle of your first knuckle to your fourth knuckle and select the closest size. Or measure the inner diameter of the bangle you currently have that fits.
Inner diameter measurement of my bangles:
Small - 56mm (very small woman or child)
Medium - 63mm (this is the average retail sized bangle)
Large - 70mm
XLarge - 76mm
If your bangle unfortunately does not fit, I do not refund on custom items where an incorrect size has been ordered.