The average ABV of a beer in the U.S. (like Coors Banquet, an American-style lager) is about 5%. A full-sized keg, also known as a half-barrel keg, holds 1,984 ounces of beer, or 15.5 gallons ...

However, these numbers represent the amount of beer in a full-sized keg ... to see at your local watering hole is referred to as a half barrel. If you want something more manageable, a quarter ...