The number of beers in one keg depends on the keg size and the beer serving size:

• A half-barrel keg (1/2 keg) holds about 15.5 gallons of beer, which equals approximately:
  • 165 beers if served in 12 oz bottles/cans,
  • 124 beers if served in 16 oz pints,
  • 99 beers if served in 20 oz servings.
• A quarter-barrel keg (1/4 keg) holds about 7.75 gallons, which equals approximately:
  • 82 beers (12 oz),
  • 62 beers (16 oz),
  • 50 beers (20 oz).
• A sixth-barrel keg (1/6 keg or sixtel) holds about 5.16 gallons, which equals approximately:
  • 55 beers (12 oz),
  • 41 beers (16 oz),
  • 33 beers (20 oz)

Regarding alcohol content, a standard 12 oz beer typically contains about 1.7 to 2.4 UK alcohol units depending on strength, with a pint of stronger lager containing about 3 units

. In the US, a standard drink contains about 14 grams (0.6 fluid ounces) of pure alcohol, roughly equivalent to one 12 oz beer of average strength

. In summary, the number of beers in "1" depends on what "1" refers to-if it's a keg, the above numbers apply; if it refers to alcohol units or standard drinks, a single 12 oz beer usually counts as one standard drink or roughly 1.7 UK units