I do not know if this helps or not, but my 15 yo son is 5'9" and 140lbs. The coat on him is a couple inches too short in the arms (he has long arms though) and slightly snug in fit. My guess is it would fit a kid who is 5'6" or shorter and 120lbs or less (but that is just my guess). I know in many cases the youth extra larges are as big or bigger than adult smalls (at least that is the case in athletic gear my son has worn over the years). Hope this help.
Last edited by Blong; 10/28/20.