A standard drink in the United States contains 0.6 fluid ounces (14 grams) of pure alcohol. That’s the fixed amount health agencies use as a baseline, regardless of what type of beverage you’re drinking. The glass size changes, but the alcohol inside stays the same.
What Counts as One Standard Drink
Three very different-looking drinks all deliver the same 14 grams of pure alcohol:
- Beer: 12 fluid ounces at about 5% alcohol by volume (ABV)
- Wine: 5 fluid ounces at about 12% ABV
- Distilled spirits: 1.5 fluid ounces (a single shot) at about 40% ABV
This is the part that trips people up. A pint glass of wine and a shot of vodka look nothing alike, but the pint holds roughly three standard drinks while the shot holds one. The container doesn’t tell you much. The math does.
How to Calculate Drinks in Any Beverage
If you know a drink’s volume in ounces and its ABV, you can figure out exactly how many standard drinks it contains. Multiply the volume by the ABV (expressed as a decimal), then divide by 0.6.
For example, a 16-ounce pint of 5% beer: 16 × 0.05 = 0.8, divided by 0.6 = 1.3 standard drinks. A 6-ounce pour of 14% wine: 6 × 0.14 = 0.84, divided by 0.6 = 1.4 standard drinks. A 750ml bottle of wine (about 25.4 ounces) at 13.5% ABV works out to roughly 5.7 standard drinks.
This formula is especially useful for cocktails. A margarita made with 3 ounces of tequila contains two full standard drinks before you account for any liqueur mixed in.
Where Craft Beer and Stronger Drinks Mislead
The standard drink framework assumes typical ABV values: 5% for beer, 12% for wine, 40% for spirits. Many popular drinks exceed those numbers. A 12-ounce craft IPA at 7.5% ABV contains 1.5 standard drinks. A double IPA at 9% in the same glass holds 1.8. Order two of those at a bar and you’ve consumed the equivalent of nearly four standard drinks, not two.
Fortified wines like port and sherry run 17% to 20% ABV. A 5-ounce glass of port at 20% contains 1.7 standard drinks. Hard seltzers usually fall closer to the baseline at 4.5% to 5%, making a 12-ounce can roughly one standard drink, though some newer versions push 8%.
Canned cocktails are particularly inconsistent. Some contain a single standard drink, others pack in two or more depending on the size and spirit content. The ABV and volume printed on the can are the only reliable guide.
How Your Body Processes One Drink
Your liver breaks down alcohol at a remarkably steady rate: about one standard drink per hour. That pace doesn’t change based on your coffee intake, how much water you drink, or whether you eat afterward. Time is the only thing that clears alcohol from your bloodstream.
When you drink faster than one per hour, the excess alcohol keeps circulating through your blood. This is what intoxication actually is: a backlog your liver can’t keep up with. A blood alcohol concentration of 0.08%, the legal limit for driving in most U.S. states, is roughly equivalent to one-eighth of a drop of alcohol per 1,000 drops of blood. It doesn’t take much.
Body weight, biological sex, food in your stomach, and genetics all affect how quickly your BAC rises per drink. But they don’t change the liver’s processing speed on the way back down.
Calories in a Standard Drink
Pure alcohol contains 7 calories per gram, nearly as calorie-dense as fat (9 calories per gram) and almost double the calories in protein or carbohydrates (4 per gram). The alcohol alone in a single standard drink accounts for about 98 calories before you add anything else: the sugars in beer, the residual sugar in wine, the mixers in a cocktail.
A 12-ounce regular beer typically lands around 150 calories total. A 5-ounce glass of dry wine runs 120 to 130. A shot of plain spirits sits near 100. But a frozen margarita or a piña colada can easily exceed 300 to 500 calories because of the added sugar and cream.
Current U.S. Drinking Guidelines
The Dietary Guidelines for Americans recommend no more than two drinks per day for men and one drink per day for women. This is a daily ceiling, not an average. Saving up all week’s “allowance” for Saturday doesn’t work the same way metabolically: your liver still processes only one drink per hour regardless of how many you had earlier in the week.
These guidelines also make clear that not drinking at all is a perfectly valid choice, and that less is generally better from a health standpoint. The one-to-two drink framework represents a moderate-risk threshold, not a target to aim for.