When choosing an alcoholic drink, the proof is a quick way to gauge its potency. A bottle of whiskey marked 120 proof is 60% ABV, letting you know it's stronger than a 40 proof (20% ABV) liqueur.

All spirits count proof among the factors that classify them. Proof doesn't factor into beverages like beer, hard seltzer, ready-to-drink cocktails, or wine, even when it's fortified wine, made ...