One standard drink in the United States contains 0.6 fluid ounces (14 grams) of pure alcohol. That works out to 12 ounces of regular beer, 5 ounces of wine, or 1.5 ounces of distilled spirits. These three servings look very different in a glass, but they all deliver the same amount of alcohol to your body.
The Three Common Equivalents
The simplest way to remember a standard drink is by these three benchmarks:
- Beer: 12 ounces at 5% alcohol by volume (ABV), which is one typical can or bottle of regular beer.
- Wine: 5 ounces at 12% ABV, roughly the amount that fills a wine glass to just below halfway.
- Distilled spirits: 1.5 ounces at 40% ABV (80 proof), a single shot of gin, rum, vodka, tequila, or whiskey.
The key number behind all of these is 14 grams of pure alcohol. Each drink type has a different concentration, so the serving size adjusts accordingly. Beer is relatively weak, so you get a full 12-ounce can. Spirits are strong, so a shot glass is all it takes to reach that same 14 grams.
Drinks That Don’t Fit the Standard Sizes
Not every alcoholic beverage falls neatly into the beer, wine, or spirits categories. The NIAAA provides additional benchmarks for less common drinks:
- Malt liquor or hard seltzer: 8 to 10 ounces equals one standard drink, because malt beverages typically run higher in alcohol than regular beer.
- Fortified wine (sherry, port): 3 to 4 ounces, since fortification pushes the ABV well above table wine.
- Cordials, liqueurs, or aperitifs: 2 to 3 ounces, as these sweet drinks often sit around 20 to 30% ABV.
- Brandy or cognac: 1.5 ounces, the same as a standard shot of spirits.
Craft beers deserve special attention. Many IPAs and stouts run 7 to 10% ABV or higher, meaning a single 12-ounce can could contain 1.5 to 2 standard drinks rather than one. The label on the can is your best guide.
How to Calculate Standard Drinks in Any Container
If you’re holding a drink and want to know exactly how many standard drinks it contains, you can use a simple formula: multiply the total volume in ounces by the ABV (as a decimal), then divide by 0.6. For example, a 16-ounce pint of craft beer at 7% ABV would be 16 × 0.07 ÷ 0.6, which equals 1.87 standard drinks.
For spirits labeled by proof instead of ABV, divide the proof number in half to get the ABV. A 90-proof bourbon is 45% ABV. A 1.5-ounce pour of that bourbon would be 1.5 × 0.45 ÷ 0.6, or 1.125 standard drinks, slightly more than one.
Why Your Actual Pour Is Probably Bigger
The standard drink is a measurement tool, not a reflection of what you’re actually served. Restaurant wine pours typically start at 5 ounces for a standard glass, but many wine bars and restaurants offer 6- to 9-ounce pours. A 9-ounce glass of wine is nearly two standard drinks, not one. Cocktails at bars commonly use more than 1.5 ounces of spirits, and many contain multiple types of alcohol. A margarita or Long Island iced tea can easily hold two to three standard drinks in a single glass.
Home pours tend to be even less precise. Studies on self-pouring consistently show that people overshoot the standard serving size for wine, beer, and spirits. If you’re pouring wine into a large-bowled glass, it’s easy to double the 5-ounce mark without realizing it. Pouring into a measuring cup once can be a useful reality check.
How Long One Drink Takes to Process
Your liver breaks down alcohol at a fairly fixed rate, lowering your blood alcohol concentration by about 0.015 per hour. For most men, that translates to roughly one standard drink per hour. Women and people with smaller body mass generally process alcohol more slowly, meaning the same single drink produces a higher blood alcohol level and takes longer to clear.
Food in the stomach, medications, liver health, and body composition all influence how fast alcohol hits your bloodstream and how quickly it leaves. But no amount of coffee, water, or cold showers changes the liver’s processing speed. If you’ve had three standard drinks, it will take your body approximately three hours (or longer) to fully metabolize the alcohol.
Standard Drinks Vary by Country
The 14-gram U.S. standard is not universal. Countries define a “standard drink” anywhere from 8 to 23.5 grams of pure ethanol, which creates real confusion if you’re reading health guidelines from different sources. The UK uses an 8-gram unit, designed around smaller pour sizes. Australia uses 10 grams. Canada uses 13.45 grams. When you see a guideline recommending “no more than two drinks per day,” the meaning changes depending on which country’s standard is being used.
In the U.S., the CDC defines moderate drinking as two drinks or fewer per day for men and one drink or fewer per day for women, with “drink” meaning 14 grams of pure alcohol each time.