About the Alcohol Unit Calculator
What is the Alcohol Unit Calculator?
Drinks vary widely in strength: a 650 ml bottle of strong beer contains about as much alcohol as four small pegs of whisky. This calculator converts any drink into grams of pure alcohol and standard drinks of 10 g, as used by WHO.
It also shows UK units (8 g), the calories from the alcohol and roughly how long your body takes to clear it.
How to use the Alcohol Unit Calculator
- Drink (sample: Beer, 650 ml bottle (5%))
- Number of Drinks (sample: 2)
- Custom Volume per Drink (ml) (sample: 100)
- Custom Strength (% ABV) (sample: 10)
- Press Calculate Alcohol Units (results also refresh as you type). The result card shows the Standard Drinks, along with Pure alcohol, UK units (8 g each), Calories from alcohol and Time for the body to clear it (about 1 standard drink an hour).
Formula used
Alcohol (g) = Volume (ml) × ABV % × 0.789
- 0.789 = density of ethanol in g/ml
- Standard drink = 10 g of alcohol
The liver clears roughly one standard drink per hour; nothing speeds this up.
Worked example
These are the sample values already filled in the calculator above, and the result it returns for them:
| Input | Sample value |
|---|---|
| Drink | Beer, 650 ml bottle (5%) |
| Number of Drinks | 2 |
| Custom Volume per Drink (ml) | 100 |
| Custom Strength (% ABV) | 10 |
| Result | Value |
|---|---|
| Standard Drinks | 5.1 |
| Pure alcohol | 51.3 g |
| UK units (8 g each) | 6.4 |
| Calories from alcohol | 359 kcal |
| Time for the body to clear it (about 1 standard drink an hour) | 5.1 hours |
| Note | No amount of alcohol is risk-free (WHO); never drink and drive |
Tips for using the Alcohol Unit Calculator
- A small peg in India is 30 ml and a large peg 60 ml.
- Keep at least two alcohol-free days a week if you drink.