The size for these sandals does not have to be exact but it is good to be close (with-in a 1/2 size).

For instance size 10 1/2 men will work well for someone who is a size 11 or a size 10.

Size Conversion Chart

These sandals are often used in Asian Cultures to activate pressure points in the foot. These pressure points are said to correlate with different parts of the body. These sandals are often used along with acupressure and acupuncture treatments.