One of the leading causes of unintentional overconsumption is assuming that "one drink" equals "one glass or bottle". Because alcoholic beverages vary from 3.5% lagers to 15% craft IPAs and 40% spirits, health agencies worldwide standardize alcohol by grams of pure ethanol.
1. What Is Pure Ethanol Mass?
Ethanol has a liquid density of 0.789 g/mL. To calculate the exact pure alcohol mass in any beverage:
2. Global Standard Drink Definitions by Country
| Country / Region | Standard Name | Pure Ethanol (Grams) | Pure Ethanol (mL) |
|---|---|---|---|
| United States | 1 Standard Drink | 14.0 g | 17.7 mL |
| United Kingdom | 1 Unit | 8.0 g | 10.0 mL |
| Australia & New Zealand | 1 Standard Drink | 10.0 g | 12.7 mL |
| European Union / WHO | Standard Unit | 10.0–12.0 g | 12.7–15.2 mL |
| Japan | 1 Go (Unit) | 19.75 g | 25.0 mL |
3. Common Beverage Equivalents (Beer, Wine, Spirits)
In the United States (14g benchmark), each of the following equals approximately 1 standard drink:
- Regular Beer: 12 fluid ounces (355 mL) at 5.0% ABV
- Table Wine: 5 fluid ounces (148 mL) at 12.0% ABV
- Distilled Spirits (80 Proof): 1.5 fluid ounces (44 mL) of Vodka, Whiskey, Gin, or Tequila at 40.0% ABV
- Fortified Wine (Port / Sherry): 3 to 4 fluid ounces (100 mL) at 17.0% ABV
4. The High-ABV Craft Beer Trap
A single 16 oz (pint) can of Double IPA at 9.0% ABV contains:
473 mL × 0.09 × 0.789 = 33.6 grams of pure ethanolThis equals 2.4 US standard drinks in just one can! Drinking two pints of craft IPA delivers nearly 5 standard drinks into your system.
Frequently Asked Questions
Evidence-based answers on alcohol clearance, testing windows, and legal limits.
In the United States, 1 standard drink contains exactly 14.0 grams (0.6 fluid ounces or 17.7 mL) of pure ethanol.