Keg Info

Description US gal 12 oz Servings 16 oz Servings Cases
Half Barrel / Full Keg 15.5 165 124 6.89
1/4 Keg 7.75 82 62 3.44
Sixth Barrel 5.23 56 42 -
European Keg 13.2 140 105 -
Mini Keg 1.32 14 10.6 -
Soda 5 53 40 -

Specifications for a U.S. 1/2 barrel keg
Height of keg 23.3 inches
Diameter of keg 16.1–17.15627 inches
Contents 1984.0 U.S. fluid ounces
15.5 U.S. gallons
12.91 imp. gallons
58.7 liters
Full keg weight 160.5 pounds (72.8 kg)
Empty keg weight 29.7 pounds (13.5 kg)
Beer weight 130.8 pounds (59.3 kg)
24×12 fl oz case equivalent 6.9 cases
12 fl oz servings 165.333
16 fl oz (1 U.S. pint) servings 124

Source of this information: http://en.wikipedia.org/wiki/Keg