Glasses of wine, martini, whiskey, and a shot

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When the goal is to drink socially and avoid drunkenness, sipping on a glass of wine seems like the right choice. If someone offers you a shot, you're likely to give it a hard pass — but it's actually the same amount of alcohol as what's in your wine glass. According to the National Institute of Alcohol Abuse and Alcoholism, a standard glass of wine is 5 ounces at about 12% alcohol by volume (ABV), and this is the equivalent of a 1½-ounce shot of 40% ABV liquor.

Wine has a lower ABV than liquor, but because you're drinking over three times the volume, it discreetly adds up. If you're drinking liquor straight up as a shot, it tastes much more concentrated and intense than a glass of wine, but the smaller volume translates to the same amount of alcohol.

This may change if standard serving sizes aren't followed. A generous pour of wine measuring 6 or 7 ounces will contain more alcohol than a 1½-ounce shot. In restaurants and bars, it can be difficult to calculate how much wine is actually sitting in your glass, especially when large wine glasses are used. Not all establishments adhere to the same serving size, either. Shot glasses to serve liquor are more standardized, but proper measurements can go out the window if the bartender is making a cocktail and not using a jigger to measure each time.

The type of wine and liquor matters when comparing alcohol content

Pouring shots of tequila with salt and lime

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The "one shot equals one glass of wine" rule works best as a general guideline because not all wines and liquors have the same alcohol content. White wines, rosés, and sparkling wines typically sit around 12% ABV, but some, like Riesling, are lower, at 8 to 9%. Many red wines are higher at 13%, and something like a Zinfandel can be up to 16% ABV. Fortified wines like Port and sherry are closer to 20% — but these are served in smaller amounts, typically between 3 and 4 ounces.

Liquors that are commonly drunk as a straight shot include vodka, rum, tequila, and whiskey. These are almost always 40% ABV, or 80-proof. Certain liquors, like cask-strength whiskeys and overproof rums, can reach over 50% ABV. Some flavored vodkas and liquors are lower at around 30 to 40%, depending on the brand. Shooters, which are different than straight shots, can be incredibly tricky to pin down, especially when they're made with a blend of liquor, high-proof spirits, and schnapps with varying ABVs.

If you're trying to monitor your alcohol intake, it's best to stick to more standard drinks, like a straight shot rather than a shooter or mixed drink. You can always ask servers or bartenders what percentage a wine is, or how many shots go into a cocktail, to better keep track of your consumption.