One US standard drink contains 14 grams (about 0.6 fl oz) of pure alcohol: a 12 oz beer at 5%, a 5 oz glass of wine at 12% or a 1.5 oz shot of 40% spirits, according to the National Institute on Alcohol Abuse and Alcoholism (NIAAA). Stronger or bigger drinks count as more than one: a 16 oz can of 7% IPA is 1.87 standard drinks.
It is for anyone who wants to count what they drink by alcohol content rather than by glasses. You need each drink's serving size and the ABV from the label; it returns US standard drinks, grams of alcohol and UK units, and totals your week against NIAAA's heavy-drinking definition.
How to use this calculator
- Pick a drink, or choose Custom. Presets fill in a typical size and ABV; change either to match your label.
- Enter the serving size in US fluid ounces or milliliters, and the alcohol by volume (ABV) printed on the can, bottle or menu.
- Read the standard drinks per serving, grams of pure alcohol and UK units.
- Enter servings per drinking day and drinking days per week to see your weekly total and whether it meets NIAAA's heavy-drinking line for men or women.
The standard drink formula
Standard drinks = volume (mL) × ABV ÷ 100 × 0.789 g/mL ÷ 14 g
- Volume × ABV gives milliliters of pure alcohol. 1 US fl oz = 29.5735 mL (NIST).
- 0.789 g/mL is the density of ethanol: 0.7893 g/cm³ at 20 °C (PubChem, citing the CRC Handbook). It turns mL of alcohol into grams.
- 14 g is the US standard drink (NIAAA). With this density, NIAAA's beer, wine and spirits examples each come to 1.00 standard drink.
- UK units = ABV × mL ÷ 1,000, where 1 unit = 10 mL or 8 g of pure alcohol (NHS).
Worked examples
A 16 oz craft IPA at 7%
16 × 29.57 = 473.2 mL. 473.2 × 0.07 × 0.789 = 26.1 g of alcohol ÷ 14 = 1.87 standard drinks, or 3.3 UK units.
A 750 mL bottle of 13% wine
750 × 0.13 × 0.789 = 76.9 g ÷ 14 = 5.5 standard drinks (9.8 UK units).
A 12-pack of 5% beer over a week
12 × 1 = 12 standard drinks a week. That is under the 15-a-week heavy-drinking line for men but over the 8-a-week line for women (NIAAA).
Standard drinks in beer by size and ABV
US standard drinks (14 g of alcohol each) for common can and pint sizes; read across from the ABV on the label:
| ABV | 12 oz can | 16 oz pint | 19.2 oz can | 24 oz can |
|---|---|---|---|---|
| 4% | 0.8 | 1.07 | 1.28 | 1.6 |
| 5% | 1 | 1.33 | 1.6 | 2 |
| 6% | 1.2 | 1.6 | 1.92 | 2.4 |
| 7% | 1.4 | 1.87 | 2.24 | 2.8 |
| 8% | 1.6 | 2.13 | 2.56 | 3.2 |
| 9% | 1.8 | 2.4 | 2.88 | 3.6 |
| 10% | 2 | 2.67 | 3.2 | 4 |
Standard drinks in wine
Common pours, from a small 125 mL glass to a full bottle, at typical wine strengths. Pours vary, so check the size you are actually served:
| Pour | 11% | 12% | 13.5% | 15% |
|---|---|---|---|---|
| 125 mL (4.2 oz) | 0.77 | 0.85 | 0.95 | 1.06 |
| 150 mL (5.1 oz) | 0.93 | 1.01 | 1.14 | 1.27 |
| 175 mL (5.9 oz) | 1.08 | 1.18 | 1.33 | 1.48 |
| 250 mL (8.5 oz) | 1.55 | 1.69 | 1.9 | 2.11 |
| 750 mL bottle | 4.65 | 5.07 | 5.71 | 6.34 |
Standard drinks in spirits
Shots and bottle sizes at common strengths; proof is twice the ABV:
| Amount | 35% (70 proof) | 40% (80 proof) | 50% (100 proof) |
|---|---|---|---|
| 1 oz | 0.6 | 0.7 | 0.8 |
| 1.5 oz shot | 0.9 | 1 | 1.3 |
| 2 oz double | 1.2 | 1.3 | 1.7 |
| 375 mL | 7.4 | 8.5 | 10.6 |
| 750 mL fifth | 14.8 | 16.9 | 21.1 |
| 1.75 L handle | 34.5 | 39.5 | 49.3 |
Common drinks in US standard drinks and UK units
The calculator's presets, including NIAAA's four one-drink examples, shown in both systems:
| Drink | Pure alcohol | US standard drinks | UK units |
|---|---|---|---|
| Regular beer, 12 oz (5%) | 14 g | 1 | 1.8 |
| Malt liquor, 9 oz (7%) | 14.7 g | 1.05 | 1.9 |
| Table wine, 5 oz (12%) | 14 g | 1 | 1.8 |
| Spirits, 1.5 oz shot (40%) | 14 g | 1 | 1.8 |
| US pint of beer, 16 oz (5%) | 18.7 g | 1.33 | 2.4 |
| Craft IPA, 16 oz can (7%) | 26.1 g | 1.87 | 3.3 |
| Hard seltzer, 12 oz (5%) | 14 g | 1 | 1.8 |
| Bottle of wine, 750 mL (13%) | 76.9 g | 5.49 | 9.8 |
| UK pint of lager, 568 mL (5.2%) | 23.3 g | 1.67 | 3 |
| UK standard wine glass, 175 mL (12%) | 16.6 g | 1.18 | 2.1 |
Weekly totals: what the guidelines say
- Dietary Guidelines for Americans, 2025–2030: “Consume less alcohol for better overall health.” Pregnant women, people in recovery from alcohol use disorder or who can't control their drinking, and people whose medicines or conditions interact with alcohol should avoid it completely. The new edition sets no daily number.
- NIAAA heavy drinking: men 5+ drinks on any day or 15+ a week; women 4+ on any day or 8+ a week.
- NIAAA binge drinking: about 5+ drinks for men or 4+ for women in about 2 hours.
- NHS (UK): no more than 14 units a week, spread over 3 or more days.
Common mistakes
- Counting glasses, not alcohol. A generous wine pour can be more than 5 oz, and a 16 oz craft beer can be nearly two standard drinks.
- Mixing US drinks and UK units. A US standard drink (14 g) is 1.75 UK units (8 g each).
- Using proof as ABV. US proof is twice the percentage of alcohol by volume (27 CFR 5.1), so 80 proof is 40%.
- Guessing cocktails. Add up each spirit in the recipe; a cocktail with 3 oz of 40% spirits is 2 standard drinks.
If you are worried about how much you drink, the SAMHSA National Helpline (1-800-662-4357) is free and confidential. This page is general information, not medical advice.
To convert bottle sizes, use the mL to oz converter, or to plan calories, the EER calculator.
Frequently asked questions
How many standard drinks are in a beer?
A 12-ounce regular beer at 5% ABV is 1 US standard drink (NIAAA). A 16 oz pint of 5% beer is 1.33, a 16 oz can of 7% IPA is 1.87 and a 12 oz beer at 8% is 1.6.
How many standard drinks are in a bottle of wine?
A 750 mL bottle of 12% wine holds 5.1 standard drinks; at 13.5% it is 5.7 and at 14.5% it is 6.1. That is about five 5-ounce glasses.
How many standard drinks are in a fifth of vodka?
A 750 mL bottle of 40% (80 proof) spirits contains 16.9 standard drinks, about 17 shots of 1.5 oz. A 1.75 L handle holds 39.5.
How many grams of alcohol are in a standard drink?
In the United States, 14 grams of pure alcohol, about 0.6 fluid ounces (NIAAA). The UK unit is smaller: 8 grams or 10 mL (NHS). One US standard drink is 1.75 UK units. The NHS unit formula is ABV × mL ÷ 1,000, so a 175 mL glass of 12% wine is 2.1 units — worth knowing when comparing US and UK advice, which count different amounts.
How do you calculate standard drinks?
Multiply the volume in mL by the ABV as a decimal to get mL of pure alcohol, multiply by 0.789 g/mL to get grams, then divide by 14. For a 5 oz glass of 12% wine: 147.9 mL × 0.12 × 0.789 = 14 g, which is 1.0 standard drink.
How many drinks a week is heavy drinking?
NIAAA defines heavy drinking as, for men, 5 or more drinks on any day or 15 or more per week, and for women, 4 or more on any day or 8 or more per week. Binge drinking is a separate pattern: enough in one sitting to bring blood alcohol to 0.08% or higher, typically 5 or more drinks for men or 4 or more for women in about 2 hours. You can stay under the weekly line and still binge.
What do the Dietary Guidelines say about alcohol?
The Dietary Guidelines for Americans, 2025–2030 (released January 2026) say: “Consume less alcohol for better overall health.” They advise pregnant women, people recovering from alcohol use disorder or unable to control how much they drink, and people on medications or with conditions that interact with alcohol to avoid it completely.
What is the UK weekly alcohol limit?
The NHS advises men and women not to drink more than 14 units a week on a regular basis, spread over 3 or more days if you drink that much.
Is a hard seltzer a standard drink?
Only if it is 12 oz at 5%. At that size and strength it is 1 drinks; a 12 oz seltzer at 8% is 1.6 and a 16 oz can at 8% is 2.13. Check the ABV on the can.
Does this calculator estimate blood alcohol (BAC)?
No. It counts how much alcohol is in your drinks. BAC depends on body size, food, time and more, and no calculator can tell you whether you are safe to drive.
Sources & method
- NIAAA — What is a standard drink? (14 g of pure alcohol; beer, malt liquor, wine and spirits examples)
- NIAAA — Drinking levels defined (binge and heavy drinking)
- USDA & HHS — Dietary Guidelines for Americans, 2025–2030, p. 4 (Limit alcoholic beverages)
- NHS — Calculating alcohol units (1 unit = 10 mL or 8 g; ABV × mL ÷ 1,000; 14 units a week)
- PubChem (NIH) — Ethanol, CID 702: density 0.7893 g/cm³ at 20 °C (CRC Handbook)
- NIAAA Core Resource on Alcohol — Defining how much alcohol is too much (cites Dietary Guidelines 2025–2030)
- 27 CFR 5.1 — Definitions: proof = twice the percentage of alcohol by volume
- SAMHSA — National Helpline, 1-800-662-HELP (4357)
- NIST SP 811 Appendix B.8 — 1 US fluid ounce = 29.5735 mL
Results are estimates for general information. Found an error? It helps everyone — see our methodology.