Alcohol Units and Drinking Guidelines Around the World

One UK unit contains 8 g of pure alcohol; one US standard drink contains 14 g.[1][3] The names may sound interchangeable, but the measures are not. A standard drink in Australia and New Zealand contains 10 g, compared with 13.45 g in Canada.[6][8][9] Before comparing national drinking guidelines, the measures need translating. The guidelines themselves also differ, and none should be read as a promise of safety.[6][11]

What alcohol units and standard drinks mean

The measure follows the alcohol, not the glass. The NHS gives a 25 ml measure of 40% ABV whisky as one UK unit, while a 35 ml measure at the same strength contains 1.4 units. ABV means alcohol by volume, the strength used in the NHS calculation.[1]

The NHS says alcohol unit counting was introduced in the UK in 1987.[1] These are the definitions used by the named national bodies, not recommended servings. A figure in UK units cannot be substituted directly into advice expressed in US standard drinks: the underlying amount of alcohol is different.[1][3]

United Kingdom: a weekly guideline

The UK Chief Medical Officers' 2016 guideline is the same for men and women: “it is safest not to drink more than 14 units a week on a regular basis”. The expert group chose a weekly rather than a daily guideline because, in its words, “most people do not drink every day”.[2]

That weekly figure is not a target to reach or an amount to concentrate into one session. The CMOs say one or two heavy drinking episodes a week increase the risk of death from long-term illness and from accidents and injuries.[2]

The NHS separately describes more than 8 units in a single session for men, or more than 6 for women, as binge drinking. Those thresholds describe a drinking pattern, rather than an alternative set of recommended amounts.[12]

United States: read the current edition

The US Dietary Guidelines for Americans, 2025 to 2030, published in January 2026, say: “Consume less alcohol for better overall health”. That is the current wording quoted here, not the numeric daily advice from the previous edition.[5]

The 2020 to 2025 edition advised two drinks or less a day for men and one or less for women, on days when alcohol was consumed. The National Cancer Institute records that earlier advice alongside the US definition of a standard drink, 14 g of pure alcohol.[3]

Definitions of heavy drinking serve a different purpose. The CDC defines it as eight or more standard drinks a week for women or 15 or more for men; these are classification thresholds, not drinking allowances.[4]

Canada: the change in 2023

Canada's Guidance on Alcohol and Health, led by the Canadian Centre on Substance Use and Addiction and funded by Health Canada, replaced the 2011 guidelines in 2023. Its central idea is a continuum of risk, rather than the older separate weekly figures for men and women.[7]

• 2 standard drinks or fewer a week: likely to avoid alcohol-related consequences.[7]
• 3 to 6 a week: increased risk of several cancers, including breast and colon cancer.[7]
• 7 or more a week: risk of heart disease or stroke “increases significantly”.[7]

CCSA also advises not exceeding two standard drinks on any occasion. Its standard drink remains Canada's measure of 13.45 g of pure alcohol, not a UK unit.[6][7]

Health Canada's page also records the 2011 advice: no more than 10 drinks a week for women or 15 for men. Those figures belong to the older guidance and should not be presented as the 2023 recommendations.[6][7]

Australia and New Zealand: same measure, different guidance

Australia and New Zealand both define a standard drink as 10 g of pure alcohol. Their weekly and daily advice nevertheless differs: knowing the measure alone is not enough.[8][9]

Australia's National Health and Medical Research Council advises healthy adults to have no more than 10 standard drinks a week and no more than four on any one day. Its example of one standard drink is 30 ml of 40% ABV spirits.[8]

New Zealand's low-risk advice gives women no more than two standard drinks a day and 10 a week, and men no more than three a day and 15 a week. It also advises at least two alcohol-free days each week.[9]

Japan: grams are not an allowance

Japan's Ministry of Health, Labour and Welfare expresses alcohol amounts in grams. Its formula is volume in millilitres multiplied by ABV divided by 100, multiplied by 0.8.[10]

The ministry identifies lifestyle-disease risk levels of 40 g or more a day for men and 20 g or more for women. It explicitly says these figures are not individual allowances or safe limits, so they should not be set beside another country's weekly guideline as though they meant the same thing.[10]

The ministry's research table shows hypertension risk rising from any amount of alcohol for both sexes.[10] The same guidance defines 60 g or more on one occasion as heavy drinking, which it says should be avoided. The distinction is between identifying risk and recommending consumption.[10]

How to calculate UK units in whisky

Start with the whisky's stated strength and the volume actually poured. The NHS calculation needs both. Enter ABV as the percentage number: for 40% ABV, use 40, not 0.40.[1]

UK units = ABV (%) × volume (ml) ÷ 1,000.[1]

1. Read the ABV and measure the volume in millilitres.
2. Multiply those two numbers.
3. Divide the result by 1,000 to get UK units.[1]

At 40% ABV, 25 ml gives 40 × 25 ÷ 1,000 = 1 unit; 35 ml gives 1.4 units, matching both NHS examples. A 700 ml bottle at 40% ABV gives 40 × 700 ÷ 1,000 = 28 UK units. That is a bottle total, not a serving recommendation.[1]

Common mistakes when comparing drinking guidelines

Treating one glass as one unit

Glass size and strength both count. The NHS example of a 175 ml glass of 12% wine contains 2.1 UK units, while its 35 ml spirit measure contains 1.4. Counting glasses alone can misstate the total: neither “a glass” nor “a serving” tells you how much alcohol it holds.[1]

Assuming dilution removes alcohol

Adding soda, water or ice does not make the original alcohol disappear. NHMRC says it does not matter whether alcohol is mixed with soft drink, water or ice: the alcohol amount still matters. Count the whisky itself, rather than judging by the size of the mixed drink.[8]

Using units as a sobriety clock

The NHS says one unit is roughly what the average adult can process in an hour, but adds that this varies from person to person. That qualification rules out a reliable countdown based only on units consumed. See drink driving limits for the separate question of driving.[1]

Reading low-risk as risk-free

Health Canada distinguishes low-risk guidance from no-risk guidance. New Zealand's alcohol.org.nz calls a safe drinking level a myth and says that, in reality, the level is zero.[6][9] WHO's Regional Office for Europe stated in 2023 that “there is no safe amount that does not affect health”. These figures describe risk, not a boundary below which harm is impossible.[11]

What these figures cannot tell you

Read every figure with three things attached: the definition of a drink, the period covered and its purpose. Canada describes risk across a week; Australia sets a maximum for any one day alongside its weekly advice; Japan identifies daily disease-risk levels, not allowances. These are different questions, not interchangeable answers about safety.[7][8][10]

For the evidence behind the risk language, read whisky and health and alcohol and cancer. People who are pregnant or trying to conceive, taking medicines that interact with alcohol, living with conditions made worse by alcohol, recovering from alcohol dependence or driving should not drink. The only safe amount before driving is none.

For personal medical advice, speak to a doctor, pharmacist or midwife. If you may be dependent on alcohol, do not stop suddenly without medical advice: seek help from a healthcare professional.

Where to go next

• Alcohol and Pregnancy: Official Guidance: national advice for pregnancy, separate from general drinking guidelines.
• Alcohol and Medicines: Interaction Risks: why medicine-specific advice needs its own consideration.
• Alcohol Dependence and Where to Get Help: guidance and support for concerns about dependence.

Sources

1. NHS. Alcohol units. Web edition, checked November 2026. https://www.nhs.uk/live-well/alcohol-advice/calculating-alcohol-units/
2. Department of Health and Social Care. UK Chief Medical Officers' Low Risk Drinking Guidelines. 2016 edition. https://assets.publishing.service.gov.uk/media/5a80b7ed40f0b623026951db/UK_CMOs__report.pdf
3. National Cancer Institute. Alcohol and Cancer Risk. Fact sheet, web edition checked November 2026. https://www.cancer.gov/about-cancer/causes-prevention/risk/alcohol/alcohol-fact-sheet
4. Centers for Disease Control and Prevention. Alcohol Use and Your Health. Web edition, checked November 2026. https://www.cdc.gov/alcohol/about-alcohol-use/index.html
5. US Department of Health and Human Services and US Department of Agriculture. Dietary Guidelines for Americans, 2025 to 2030. January 2026 edition. https://cdn.realfood.gov/DGA_508.pdf
6. Health Canada. Canada's Low-Risk Alcohol Drinking Guidelines. Web page recording the 2011 guidelines, checked November 2026. https://www.canada.ca/en/health-canada/services/substance-use/alcohol/low-risk-alcohol-drinking-guidelines.html
7. Canadian Centre on Substance Use and Addiction. Canada's Guidance on Alcohol and Health. 2023 guidance, supporting web page checked November 2026. https://www.ccsa.ca/canadas-guidance-alcohol-and-health
8. National Health and Medical Research Council, Australia. Alcohol. Web edition, checked November 2026. https://www.nhmrc.gov.au/health-advice/alcohol
9. alcohol.org.nz, New Zealand. Low-risk alcohol drinking advice. Web edition, checked November 2026. https://www.alcohol.org.nz/help-advice/advice-on-alcohol/low-risk-alcohol-drinking-advice
10. Ministry of Health, Labour and Welfare, Japan. 健康に配慮した飲酒に関するガイドライン (Guideline on drinking with consideration for health). Supplied PDF edition, publication date not established in the fact sheet; checked November 2026. https://www.mhlw.go.jp/content/12200000/001211974.pdf
11. WHO Regional Office for Europe. No level of alcohol consumption is safe for our health. 4 January 2023. https://www.who.int/europe/news/item/04-01-2023-no-level-of-alcohol-consumption-is-safe-for-our-health
12. NHS. The risks of drinking too much. Web edition, checked November 2026. https://www.nhs.uk/live-well/alcohol-advice/the-risks-of-drinking-too-much/

Prepared as desk research from the site's verified fact sheet and the national and international guidance listed above.

Last checked: November 2026