Measuring your unique bodily phi size is a simple process that anyone at home equipped with a ruler or tape measure can execute. If you are not equipped with any sort of measuring device, please print out our ruler PDF for your convenience.
Using the backside of your thumb, measure the tip of your bent, middle knuckle to the tip of your finger (minus your nail). Try to be as exact as possible landing between or on 3.5 to 4.5 centimeters. The final reading is your bodily phi measurement and should be ordered in that size after adding your mat to cart.