What is a "standard drink"?

A standard drink is a unit used by health authorities to measure alcohol consumption. It represents a specific amount of pure alcohol — but the exact amount differs by country: the US defines it as 14 g of pure alcohol (NIAAA), the UK as 8 g (one "unit", NHS), Australia and Singapore as 10 g, and Canada as 13.45 g (CCSA). Because these definitions differ, a single glass of wine may count as 1 standard drink in one country and more than 1 in another.

Can I use this calculator to find out if I am safe to drive?

No. This tool converts alcohol volume and ABV into standard drinks and pure alcohol grams — it does not estimate blood alcohol concentration (BAC) or assess fitness to drive. Standard drink counts are a health reference tool; they are not a measure of intoxication. If you need an estimated BAC figure, use the BAC Calculator. Regardless of any calculation, the only safe BAC for driving is 0.000%.

Why do different countries define standard drinks differently?

Each country's health authority independently set their own definition when developing national alcohol guidelines and public health messaging. There is no international consensus. The amounts range from 8 g (UK) to 14 g (US), reflecting different policy decisions about what constitutes a meaningful and communicable unit of measurement for their populations. When comparing guidelines across countries, always check which definition was used.

Standard Drinks / Alcohol Units Calculator

Drink Details

Drink Type

ABV (%)

Volume

Country Standard

Standard drink definitions differ by country. Select the one that applies to you.

Standard Drinks (US (14 g))

1.00drinks

Pure Alcohol

14.00g

Calories (alcohol only)

98kcal

approx. — alcohol only, not total beverage

Weekly recommended upper limit — US (NIAAA (National Institute on Alcohol Abuse and Alcoholism))

≤ 14 drinks/week (men) · ≤ 7 drinks/week (women)

These are general guidelines — individual health conditions, medications, and other factors may require lower or no alcohol consumption. Consult a healthcare professional for personal advice.

This tool converts alcohol content to standard drinks only — it does not estimate blood alcohol concentration (BAC). Use the BAC Calculator if you need an estimated BAC figure.

About This Tool

Convert any drink's volume and ABV into standard drinks (US, UK, AU/SG, Canada) and pure alcohol grams. See how many units your drink contains according to your country's health guidelines — for reference only. All calculations run in your browser.

Standard drink definitions vary by country. The US defines one standard drink as 14 g of pure alcohol (NIAAA), the UK as 8 g (one “unit”, NHS), Australia and Singapore as 10 g, and Canada as 13.45 g (CCSA). This tool converts any drink's volume (mL or fl oz) and ABV% into standard drinks, pure alcohol grams, and approximate alcohol-derived calories under each country's definition.

This tool is a pure alcohol conversion reference — it does not estimate blood alcohol concentration (BAC) or assess fitness to drive. Use the BAC Calculator if you need an estimated BAC.

How To Use

Select a drink type — choosing a preset automatically fills in the ABV% and a typical serving volume.
Adjust volume and ABV if needed — switch between mL and fl oz, and edit the ABV% directly for custom drinks.
Choose a country standard— select US, UK, AU/SG, or Canada to apply that country's definition.
Read the result — standard drinks, pure alcohol grams, and approximate calories are shown instantly.

Example Calculation

Example: Regular beer 355 mL, 5% ABV — comparing US and UK standards

• Pure alcohol = 355 mL × 5% × 0.789 g/mL ≈ 14.01 g

• US standard (14 g/drink): 14.01 ÷ 14 ≈ 1.00 standard drinks

• UK standard (8 g/unit): 14.01 ÷ 8 ≈ 1.75 units

• Alcohol calories ≈ 14.01 × 7 ≈ 98 kcal

The same drink counts differently depending on which country standard you use. Calories shown are from alcohol (ethanol) only — calories from sugar, carbohydrates, and other beverage components are not included.

Frequently Asked Questions

What is a "standard drink"?: A standard drink is a unit used by health authorities to measure alcohol consumption. It represents a specific amount of pure alcohol — but the exact amount differs by country: the US defines it as 14 g of pure alcohol (NIAAA), the UK as 8 g (one "unit", NHS), Australia and Singapore as 10 g, and Canada as 13.45 g (CCSA). Because these definitions differ, a single glass of wine may count as 1 standard drink in one country and more than 1 in another.
Can I use this calculator to find out if I am safe to drive?: No. This tool converts alcohol volume and ABV into standard drinks and pure alcohol grams — it does not estimate blood alcohol concentration (BAC) or assess fitness to drive. Standard drink counts are a health reference tool; they are not a measure of intoxication. If you need an estimated BAC figure, use the BAC Calculator. Regardless of any calculation, the only safe BAC for driving is 0.000%.
Why do different countries define standard drinks differently?: Each country's health authority independently set their own definition when developing national alcohol guidelines and public health messaging. There is no international consensus. The amounts range from 8 g (UK) to 14 g (US), reflecting different policy decisions about what constitutes a meaningful and communicable unit of measurement for their populations. When comparing guidelines across countries, always check which definition was used.

This calculator provides approximate reference figures based on alcohol unit conversion formulas — it is not medical advice or a clinical assessment. The actual health impact of alcohol varies by individual constitution, health status, and medications. If you are pregnant, have liver disease or other health conditions requiring caution around alcohol, or need guidance on alcohol consumption for health reasons, please consult a healthcare professional. This tool does not recommend alcohol consumption or endorse any specific quantity as safe.

This calculator is for informational purposes only and does not constitute medical advice. Results are estimates based on general formulas. Always consult a qualified healthcare professional for health-related decisions.

Related Tools

BAC Calculator (Blood Alcohol Concentration)

Estimate your Blood Alcohol Concentration (BAC) using the Widmark formula. Enter your sex, weight, drinks consumed, and time elapsed to get an instant estimate — for informational reference only. Never use this to judge fitness to drive.