Standard drink calculator
Enter the drink size and alcohol percent, count standard drinks.
What is a standard drink in the US?
Any drink with about 14 grams — 0.6 fluid ounces — of pure alcohol (NIAAA). That is 12 fl oz of regular beer at about 5%, 5 fl oz of wine at about 12%, or 1.5 fl oz of 80-proof spirits.
How do I count standard drinks?
Multiply the fluid ounces by the alcohol percent and divide by 0.6: a 16 fl oz craft beer at 7% has 16 × 0.07 ÷ 0.6 = 1.9 standard drinks.
When is a glass of wine more than one drink?
When the pour is larger than 5 fl oz or the wine is stronger than 12%. A 9 fl oz pour at 13.5% is about 2 standard drinks.
What do the Dietary Guidelines say about alcohol?
The 2025–2030 Dietary Guidelines advise consuming less alcohol for better overall health, and say some people should avoid it completely, including pregnant women. The earlier 2020–2025 edition gave limits of 2 drinks or less a day for men and 1 or less for women.
Does a standard drink affect everyone the same?
No — body size, sex, food and medications all change the effect. This calculator counts alcohol; it cannot estimate blood alcohol or whether it is safe to drive.
How many standard drinks are in a bottle of wine?
A 750 mL bottle is 25.4 fluid ounces. At 13.5% alcohol it holds 5.7 US standard drinks (80 grams of pure alcohol); at 12% it holds 5.1. A 750 mL bottle of 80-proof (40%) spirits holds about 17.
What is the difference between proof and percent alcohol?
In the US, proof is twice the alcohol by volume: 80 proof is 40% ABV. Enter the percentage, not the proof. Entering 80 as the percent would give a result twice as large as it should be.
Is a standard drink the same in other countries?
No. The US figure is 14 grams of pure alcohol. Other countries use different amounts; for example, the UK unit is 8 grams and an Australian standard drink is 10 grams. A US standard drink is therefore a little under two UK units, and results from this page cannot be compared with another country's guidance without converting.
How the count is calculated
A US standard drink contains 0.6 fluid ounces of pure alcohol, which is about 14 grams. To find how many you have, multiply the volume by the alcohol percentage as a decimal and divide by 0.6. The mass is the volume of pure alcohol times its density, 0.789 grams per milliliter. The calculator accepts fluid ounces or milliliters (1 fl oz is 29.5735 mL) and a number of identical drinks. It treats the label percentage as exact, although real products may differ slightly from their labels.
Worked example: beer, wine and a spirit
A standard 12 fl oz beer at 5% has 12 × 0.05 ÷ 0.6 = 1.0 drink (14.0 g of alcohol). A 16 fl oz craft beer at 7% has 1.9 drinks (26.1 g). A restaurant pour of 9 fl oz of wine at 13.5% has 2.0 drinks (28.4 g), which is why one glass can count as two. The same count in grams is a useful check: divide the grams by 14 and you get the same number of drinks.
Why servings are bigger than they look
The reference sizes in the table under the result (12 oz of beer, 5 oz of wine, 1.5 oz of 80-proof spirits) are smaller than many real servings. A pint glass is 16 fluid ounces, a generous wine pour can be 8 or 9, and mixed drinks often contain two shots. Higher-strength beers, ciders and hard seltzers shift the count too. Counting from the actual volume and the label strength is more reliable than counting glasses.
Common mistakes
Treating any glass as one drink is the main one. Another is entering proof instead of percent. A third is mixing units: 750 is milliliters, not ounces, so switch the unit before entering a bottle. The count is also not a measure of impairment: blood alcohol depends on body weight, sex, food, time and other factors, and no calculator that only counts drinks can say whether it is safe to drive.
Sources: National Institute on Alcohol Abuse and Alcoholism (NIAAA), "What is a standard drink?" (14 grams, 0.6 fluid ounces of pure alcohol, and the reference serving sizes); ethanol density 0.789 g/mL; NIST SP 811 for the fluid ounce. Information only, not medical advice. Related: blood alcohol calculator, ABV calculator and calorie calculator.
For general information only — not medical advice. Talk with your doctor or another health professional about your own health. How we check our calculators.