The average weight airlines allow for a checked bag for airlines without an additional fee is 50 lbs. The maximum weight allowed for checked bags even with a fee is 70 lbs.
Most airlines only regulate the size of a carry-on baggage and do not set a limit on the weight of a carry-on item. However, some airlines such as Delta limit carry on baggage to only 11 lbs.
Should your checked baggage be over the airline's weight limit, a fee may be accessed for the additional pounds. Each airline has its own pricing schedule for overweight baggage, but the average fee is $50 per piece that is overweight.