The weight of a punching bag depends entirely on the height and weight of a user, if a person belongs to a light weight then the weight of the bag will be between 50-70 pounds and if a user belongs to heavyweight then the bag will weigh between 80-100 pounds. Besides the weight, height of the bag is also important. Normally 4ft and 5ft bags are available, if you are over 6 feet than it is better to use 5ft bag, if you are shorter than a 4ft bag will do just fine.