how many sizes of kegs are there

There are usually 7 common keg sizes people mean when they ask this, though exact naming can vary by country and brewer.

Common keg sizes

• Cornelius keg, about 5 gallons.
• Sixth-barrel keg, about 5.16 gallons.
• Quarter-barrel keg, about 7.75 gallons.
• Slim quarter keg, also about 7.75 gallons.
• Half-barrel keg, about 15.5 gallons.
• 50-liter keg, about 13.2 gallons.
• Mini keg, about 1.5 gallons.

What people usually mean

In the U.S., the half-barrel keg is the standard “full keg” most people picture, and smaller party kegs like the quarter-barrel and sixtel are also common. Outside the U.S., 50-liter kegs are widely used, especially in Europe and the UK.

Quick answer

So the short answer is: about seven mainstream sizes , depending on whether you count regional and mini formats.