How many beers are in a keg? Your guide to the gallon sizes of 7 different keg types.

The origins of beer date to before 6000 CE in Sumer and Babylonia or modern-day’s southern Iraq, according to Britannica. Made from fermented barley or other grains, beer was believed to be a nutrient-rich beverage for the early civilizations and deemed safer than contaminated river or canal water.

Over the centuries, beer has become a communal drink -- a staple for social gatherings, casual get-togethers and sports watch parties. And holding all the beer, kegs have found their way into these social scenarios. If you’re hosting a party that calls for the bubbly drink, here’s how many beers a keg can hold.

How many beers in a keg?

Kegs are small barrels that can hold any type of liquid in them, but they have been most known to store, transport and serve beer. So, how many beers can they hold? According to Mental Floss, not all kegs are the same size. Depending on the size and type of keg, the quantity of beer it houses changes.

There are seven different keg sizes and types, according to the KegWorks’ guide. These include:

  • Cornelius Keg

  • Sixth Barrel Keg

  • Quarter Barrel Keg

  • Slim Quarter Keg

  • Half Barrel Keg

  • 50 Liter Keg

  • Mini Keg

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Cornelius Keg

Also known as Corny Keg and Homebrew Keg, Cornelius Keg was originally developed to store and distribute soda. This type of keg has become very popular with homebrewers, KegWorks reports. It has a capacity of 5 gallons or 18 liters and can hold approximately 53 beer cans (each 12 oz) or 40 pints (each 16 oz).

Sixth Barrel Keg

A Sixth Barrel Keg or 1/6 Barrel is slightly bigger in size when compared to Cornelius Keg. With a capacity of 5.6 gallons or 20 liters, a Sixtel – another common name for the 1/6 Barrel – can hold up to 55 bottles (each 12 oz) or 41 pints (each 16 oz) of beer. What makes a sixth barrel keg different is its use of a traditional keg valve, according to KegWorks.

Quarter Barrel Keg

Nicknamed Pony Keg and Stubby Quarter, a Quarter Barrel Keg is probably what you’ve spotted at keg parties. Although it has a short and “stubby” appearance, the quarter barrel holds more liquor than a Sixtel or a Corny Keg – about 7.75 gallons or 30 liters. A quarter barrel can hold 82 bottles (each 12 oz) or 62 pints (each 16 oz) of beer and are perfect for parties.

Slim Quarter Keg

As the name suggests, a Slim Quarter Keg is a taller and slimmer cousin of a Quarter Barrel Keg, holding the exact same amount of beer as the latter. Outside of appearance, both kegs have no big differences.

Half Barrel Keg

With a capacity of 15.5 gallons, a Half Barrel Keg -- also known as Full Size Keg or Full Keg -- is the most suited for restaurants and bars. Historically, this type of keg has been used in distributing liquor in macro breweries for generations. The keg produces 165 cans (each 12 oz) or 124 pints ( each 16 oz) of beer.

50 Litre Keg

As the name suggests, a 50 Litre Keg holds a gigantic amount of beer -- 50 liters or 13.2 gallons. Seen as a common keg size in UK and Europe, the 50 Litre Keg is used by European breweries and hold 140 cans (12 oz) or 105 pints (16 oz) of beer.

Mini Keg

A Mini Keg is the perfect size for a small gathering, according to KegWorks. The usual 12-pack can be replaced with the mini keg for not only the aesthetic appearance of a keg but also for an easier after-party clean up and possibly, a cheaper price. The mini keg has a capacity of 5 liters and holds 14 bottles (each 12 oz) or 10 pints (16 oz) of beer approximately.

How long does beer last in a keg?

According to Payless Liquors, a keg which is dispensed with carbon dioxide and holds non-pasteurized beer, can stay fresh for 45 to 60 days – granted, the pressure and temperature are maintained consistently. For pasteurized draft beers, the shelf life is around 90 to 120 days. When consumed within these timeframes, the beer retains its freshness and complements your food.

Just like other alcoholic beverages, beer is enhanced in flavor when paired with well-matching food. Of course, different types of beer call for different foods like an ale might pair well with fried food but lagers taste best with grilled meat or light seafood, according to Epicurious.

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This article originally appeared on USA TODAY: How many beers in a keg? The true size of a barrel o' beer.