Found this on housekeeping.com:

Front loading washing machines can hold as much as 18 lbs of clothing. So how many items are in a lb. of clothing? To find out how much your loads weigh, you can weigh yourself holding a load of dirty clothing, and subtract it from your weight without the dirty load. While weight varies with type of material, these are some general guidelines. Twin Sized Quilt-3-5 lbs. Complete Child Outfit-1-3 lbs. Complete Adult Outfit-3-5 lbs.