Alcohol in wine is measured in percentage by volume (% vol) and is always stated on the label. Most table wines fall between 11 and 15%. Alcohol contributes warmth, body, and a certain sweetish tapering in the finish. High alcohol without sufficient fruit, acidity, or tannin is perceived as burning and unbalanced.

Alcohol level is determined by the grape's sugar content at harvest — more sugar produces more alcohol if all the sugar ferments out. Winemakers can influence the level by harvesting early (lower sugar, lower alcohol) or late, or through technical methods such as reverse osmosis. In Europe, alcohol levels for many classified wines are regulated.