In the United States, one standard drink contains 0.6 fluid ounces (about 14 grams) of pure alcohol. That number stays the same whether you’re drinking beer, wine, or spirits. What changes is the size of the pour needed to reach that 14-gram mark.
What Counts as One Standard Drink
Because different beverages have different alcohol concentrations, the serving size for a standard drink varies quite a bit. Each of the following contains the same 0.6 ounces of pure alcohol:
- Regular beer (5% ABV): 12 ounces, a typical can or bottle
- Malt liquor (7% ABV): 8 ounces, about two-thirds of a standard pint glass
- Wine (12% ABV): 5 ounces, noticeably smaller than what most restaurants pour
- Distilled spirits (40% ABV / 80 proof): 1.5 ounces, a single shot
The math behind these numbers is straightforward. Multiply the volume of the drink by its alcohol percentage, and you get the amount of pure alcohol. A 12-ounce beer at 5% gives you 0.6 ounces of alcohol. A 5-ounce glass of wine at 12% gives you the same 0.6 ounces. The standard drink is simply a way to put all these beverages on equal footing.
Why Poured Drinks Are Rarely “Standard”
The standard drink is a measurement tool, not a reflection of how alcohol is actually served. A typical wine glass holds 8 to 12 ounces, so a generous restaurant pour can easily be 7 or 8 ounces, which is closer to 1.5 standard drinks. Cocktails made with multiple spirits might contain two or three standard drinks in a single glass. Pint glasses hold 16 ounces of beer, which is 1.3 standard drinks if you’re drinking a regular 5% lager.
Craft beers make this trickier. Many IPAs and stouts run 7% to 9% ABV or higher. A 16-ounce pint of a 9% double IPA contains nearly 2.5 standard drinks. If you’re keeping track of your intake, the ABV on the label matters as much as the number of glasses you’ve had.
How Your Body Processes One Drink
Your liver breaks down alcohol at a fairly fixed rate: roughly one standard drink per hour. That pace doesn’t change based on body size, food intake, or how much water you drink alongside your beer. Those factors affect how quickly alcohol reaches your bloodstream and how intoxicated you feel, but the liver’s processing speed stays constant.
This means that if you’re drinking faster than one standard drink per hour, alcohol accumulates in your blood. Two drinks in an hour leaves about one drink’s worth of alcohol still circulating. Three drinks in an hour leaves two. This is why the pace of drinking matters just as much as the total number.
How Standard Drinks Relate to Guidelines
U.S. health guidelines define moderate drinking as two drinks or fewer per day for men, and one drink or fewer per day for women. Those limits are built on the 14-gram standard. If you’re drinking high-ABV beverages or oversized pours, you can hit those thresholds faster than you might expect.
The gap between men’s and women’s guidelines reflects real biological differences. Women generally have less body water and produce less of the enzyme that breaks down alcohol in the stomach, so the same amount of pure alcohol produces a higher blood alcohol concentration in women than in men of similar weight.
Standard Drinks in Other Countries
The 14-gram figure is specific to the United States. Other countries define a standard drink differently, which can be confusing if you’re reading health advice from international sources. The UK standard drink is 8 grams of pure alcohol. Australia uses 10 grams. Japan uses about 19.75 grams. If you’re comparing drinking guidelines across countries, check which standard they’re using first, because “one drink” doesn’t mean the same thing everywhere.
A Quick Way to Estimate
If you want a rough calculation for any beverage, use this formula: multiply the volume in ounces by the ABV (as a decimal), then divide by 0.6. That gives you the number of standard drinks. A 16-ounce craft beer at 8% ABV: 16 × 0.08 = 1.28 ounces of pure alcohol, divided by 0.6 = about 2.1 standard drinks. A 6-ounce glass of wine at 14% ABV: 6 × 0.14 = 0.84, divided by 0.6 = 1.4 standard drinks.
Most people underestimate how much they’re actually drinking. Running the numbers even once or twice can recalibrate your sense of what “one drink” really means.