Hockey sock sizing is about as easy as it gets: it's simply measured as the length of the sock. The sock will run from your ankle to about 75% of the way up your thigh (to meet the Velcro tabs on your jock).
Since socks are simply measured according to length most brands do not have a "youth" or "adult" size.
Sock lengths do NOT measure the Velcro tabs. Some brands' Velcro tabs extent beyond the sock while others are contained entirely within them.
Please note that every brand uses different increments and labels different lengths with different sizes. Depending on which socks you are ordering from us you'll need to determine the appropriate size from the chart below