Measure the narrowest part of your waist and the widest part of your hips and buttocks.

Brand Size Waist (inch) Hip (inch)
S 26.0 - 28.5 31.5 - 33.5
M 28.0 - 30.5 32.5 - 35.0
L 30.5 - 33.5 34.0 - 38.0

Natural silk has little stretch. Size up for the best fit.