A standard drink in the United States contains about 0.6 fluid ounces of pure alcohol, which works out to roughly 14 grams. That’s the universal measuring stick, but the actual volume in your glass changes dramatically depending on what you’re drinking. A 12-ounce beer, a 5-ounce glass of wine, and a 1.5-ounce shot of liquor all contain the same amount of alcohol if they’re at typical strengths.
Standard Drink Sizes by Beverage
The reason a “standard drink” exists is to give you a consistent way to compare very different beverages. Here’s what one standard drink looks like for each major category:
- Regular beer (5% ABV): 12 fluid ounces, or one typical can or bottle
- Table wine (12% ABV): 5 fluid ounces
- Fortified wine like port or sherry (around 17% ABV): 3 fluid ounces
- Distilled spirits like vodka, whiskey, or rum (40% ABV): 1.5 fluid ounces, or one standard shot
Each of these contains the same 0.6 ounces of pure alcohol. The stronger the drink, the smaller the volume needed to reach that threshold.
Why Your Drink May Not Be “Standard”
The standard drink framework assumes typical alcohol concentrations, and plenty of popular drinks don’t fit neatly into those assumptions. A craft IPA at 7% ABV has 40% more alcohol per ounce than a 5% lager, meaning a single 12-ounce can is closer to 1.7 standard drinks. Some imperial stouts and barleywines clock in at 9% to 12% ABV, pushing a single pint well past two standard drinks.
Wine is similarly tricky. Many popular reds now sit at 14% to 15% ABV rather than the 12% used in the standard calculation. A generous restaurant pour of 6 or 7 ounces of a 15% wine could easily equal 1.5 standard drinks. Cocktails are the hardest to gauge because recipes vary widely. A margarita or a Long Island iced tea can contain two, three, or even four standard drinks depending on how it’s made.
The simplest way to estimate is to divide. Take the total fluid ounces of your drink, multiply by the ABV (as a decimal), and divide by 0.6. A 16-ounce pint of 7% beer: 16 × 0.07 = 1.12 ounces of pure alcohol, divided by 0.6 = roughly 1.9 standard drinks.
How Your Body Processes One Drink
Your liver breaks down alcohol at a remarkably steady pace: about one standard drink per hour. This rate doesn’t change much regardless of your size, tolerance, or how much water you drink alongside it. If you consume three standard drinks in an hour, your body still needs roughly three hours to fully process the alcohol.
Food slows absorption into the bloodstream, which means your blood alcohol level rises more gradually on a full stomach. But it doesn’t speed up elimination. The total processing time stays about the same. Coffee, cold showers, and exercise don’t help either. Time is the only thing that clears alcohol from your system.
Moderate Drinking Guidelines
Federal guidelines define moderate drinking as two standard drinks or fewer per day for men and one or fewer for women. These limits are based on the standard drink measurements above, so the actual volume depends on what you’re pouring. Two “drinks” of a high-ABV craft beer could easily exceed the guideline even though you only had two cans.
The difference between men and women in these guidelines reflects differences in body composition and how alcohol is metabolized. Women generally have less of the enzyme that breaks down alcohol in the stomach lining, which means more alcohol reaches the bloodstream per drink.
Standard Drinks in Other Countries
The 0.6-ounce, 14-gram definition is specific to the United States. Other countries draw the line differently. Canada defines a standard drink as containing about 13.6 grams of pure alcohol (roughly 0.58 US fluid ounces), which is close to the American measure but not identical. The UK uses a smaller “unit” system at 8 grams per unit, meaning a single pint of average-strength beer counts as about two units rather than one drink. Australia sets its standard at 10 grams.
These differences matter if you’re reading health recommendations from international sources. A guideline suggesting “no more than 10 standard drinks per week” means something very different in Australia (100 grams of alcohol) than it would using the US definition (140 grams). Always check which country’s standard is being used.