To determine your head (hat) size, measure your head as shown below, using a flexible tape measure. Measure circumference of head just above top of ears, as shown. Wrap tape gently around head making certain tape lies midway on your occipital bone (that little bump in the middle of the back of your head). Don't pull the tape too tghtly. Remember when in doubt, order the next bigger size for comfort. You now have your head (hat) size.