What is one alcohol unit?

One standard unit contains 12 grams of pure alcohol. That corresponds, for example, to a bottle (33 cl) of medium-strength beer, a glass (12 cl) of wine, or 4 cl of spirits.

How are alcohol units calculated?

The formula is: volume (ml) × alcohol percentage / 100 × 0.789 (the density of ethanol) = grams. Dividing the grams by 12 gives the number of standard units. The calculator does this automatically.

How much alcohol is too much?

According to the Finnish Institute for Health and Welfare (THL), the risk threshold is 14 units per week for men and 7 for women. Moderate use means staying clearly below these. There is no completely safe limit.

How many units are in a bottle of vodka?

A half-litre (50 cl) bottle of 40% vodka contains roughly 500 ml × 0.40 × 0.789 / 12 ≈ 13 standard units.

Alcohol Units Calculator

Calculate how many standard alcohol units your drink contains by volume and ABV. Compare to weekly limits. Free alcohol units calculator.

Juoman tilavuus: 33 cl

Alkoholiprosentti: 4.70 %

Juomien määrä: 1 kpl

1.0 annosta

Vakioannoksia yhteensä

Puhdasta alkoholia / juoma	12.2 g
Vakioannoksia / juoma	1.02 annosta
Annoksia yhteensä	1.0 annosta
Puhdasta alkoholia yhteensä	12 g

ℹ️ Yksi vakioannos = 12 g puhdasta alkoholia. THL:n riskirajat: miehet enintään 14 annosta/viikko, naiset 7. Laskuri on suuntaa-antava.

The alcohol units calculator converts a drink's volume and strength into standard units and shows how many you consume in total. You can compare the result to weekly limits and gauge your own intake.

How the calculator works and what it’s for▾

How units are calculated

The tool works out the grams of pure alcohol from the volume and percentage, then divides by the size of one standard unit. One standard unit equals 12 grams of pure alcohol.

For example, a 33 cl beer at 4.7% holds a little over one and a half units. Multiply that by the number of drinks to get the evening's total.

What you enter and what you get

Enter the drink volume in centiliters, the alcohol percentage and the number of drinks. You see the grams of pure alcohol and the units, both per drink and in total.

The several results make it easy to see how a single glass relates to the whole evening.

Weekly risk limits as a reference

As a reference, common risk guidance suggests men stay at no more than 14 units per week and women at 7. The calculator helps you relate your intake to these limits.

Such limits are indicative and do not guarantee safety — less is always safer.

Good to know

This is an indicative self-tracking tool and does not replace a health professional's assessment. Individual differences in size and metabolism affect how alcohol acts.

Use the result to understand your drinking, not as medical advice.

🔄 Reviewed June 2026