Finding your size
The robe is cut loose. Most people size down, not up.
Robes are meant to wrap, so ours is cut generously across the chest. If you're between sizes, pick the smaller one.
Length is measured from the back of the collar to the hem. On someone 5'6", the M/L lands just below the knee.
Expect about 3% shrinkage in the first warm wash, mostly in length.