Standard Drinks & Alcohol Units Calculator (UK & US)

How to use this tool

Pick a preset or adjust the volume and ABV sliders for one drink.
View the UK units, US standard drinks, pure alcohol, and ethanol-only calorie estimate.

What is one unit of alcohol?

The definition of a "unit" differs between countries:

UK unit: 10 ml (or 8 g) of pure ethanol. The formula is: units = (volume ml × ABV%) ÷ 1000
US standard drink: 14 g of pure ethanol — equivalent to 1.75 UK units.
EU/international: Varies by country, typically 10–14 g per "drink".

For a practical example: a 330 ml bottle of 5% beer = (330 × 5) / 1000 = 1.65 UK units or approximately 0.93 US standard drinks.

The ethanol-only calorie estimate uses 7 kcal per gram of pure alcohol and rounds to a whole number. It excludes carbohydrates in beer or wine and calories from mixers, so it is not the total calorie count for a drink.

Common drinks reference

Drink	Volume	ABV	UK units	US standard drinks
Pint of beer (4%)	568 ml	4%	2.3	1.3
Pint of strong lager (5.2%)	568 ml	5.2%	3.0	1.7
Glass of wine (13%)	175 ml	13%	2.3	1.3
Large glass of wine (13%)	250 ml	13%	3.3	1.9
Single spirit measure (40%)	25 ml	40%	1.0	0.6
Double spirit measure (40%)	50 ml	40%	2.0	1.1
Bottle of wine (12.5%)	750 ml	12.5%	9.4	5.3
Can of beer (330 ml, 5%)	330 ml	5%	1.7	0.9
Alcopop (275 ml, 4%)	275 ml	4%	1.1	0.6

Low-risk drinking guidelines

UK (NHS): No more than 14 units per week for both men and women. Spread over 3 or more days; have several alcohol-free days each week.
US (2025–2030 Dietary Guidelines): The guidance encourages consuming less alcohol for better overall health and says that certain groups should completely avoid alcohol.
Australia (NHMRC 2020): No more than 10 standard drinks per week and no more than 4 on any single day.

Many health organizations now emphasize that there is no completely safe level of alcohol consumption, and less is always better for health.

How alcohol is metabolized

The liver processes alcohol at approximately 1 UK unit (10 ml / 8 g) per hour for an average adult. This rate is largely fixed by the enzyme alcohol dehydrogenase (ADH) and cannot be significantly sped up by coffee, food, cold showers, or exercise — only time allows blood alcohol to fall.

Food slows absorption (gastric emptying rate), reducing the peak BAC, but does not change the elimination rate. A meal before drinking means alcohol enters the bloodstream more slowly; the same total amount is still processed over the same total time.

Frequently asked questions

What is a UK alcohol unit?

One UK unit equals 10 ml (or 8 g) of pure alcohol. The formula is: Units = Volume (ml) × ABV% ÷ 1000. UK low-risk guidelines recommend no more than 14 units per week for adults.

What is a US standard drink?

One US standard drink contains 14 grams of pure alcohol - equivalent to a 12 oz (355 ml) regular beer (5% ABV), a 5 oz (148 ml) glass of wine (12% ABV), or a 1.5 oz (44 ml) shot of spirits (40% ABV).

Is this a medical or safety tool?

No. This is an educational calculator for informational purposes only. Individual alcohol tolerance varies greatly. Do not use this to assess fitness to drive. If you have concerns about alcohol consumption, consult a healthcare professional.