A 2-gallon keg holds 256 oz (~7.57 L)
When scaling a recipe, you want your total ingredients to add up to about 7.5 liters (allowing for a bit of headspace).
Since most liquor is sold in 750 ml bottles (0.75 L) or 1 L bottles, converting your recipe into liters makes shopping and measuring simpler. Most recipes for kegged cocktails start with:
- (2) fifths (1.5 L total) or
- (1) half gallon of liquor (1.9 L)
Then fill the rest with mixers. The chart below has common measurement conversions.