What is the alcohol content of 80 proof ethanol?

The alcohol content of 80 proof ethanol is 40%. The proof system is a measure of the strength of alcoholic beverages, where proof is defined as twice the percentage of alcohol by volume (ABV). Therefore, an 80 proof beverage contains 40% alcohol by volume, which means that 40% of the liquid is pure ethanol. This standard is widely used in the United States and provides a straightforward way to understand the potency of alcoholic drinks.

Understanding proof can help consumers make informed choices about alcohol consumption, as higher proof values indicate stronger alcohol content. In this case, recognizing that 80 proof correlates directly to a 40% ABV is essential for anyone working with or consuming alcoholic beverages.