Units and calories in whisky

Whisky is a strong alcoholic drink. Legally, any whisky (or ‘whiskey') sold in the UK must be at least 40% alcohol by volume (ABV).¹ That means forty percent of the drink is pure alcohol - and if the ABV is higher, the percentage of alcohol is higher too.

In comparison beer is often around 5% ABV, so an average whisky is eight times stronger. 

To keep health risks from alcohol low, if you choose to drink, it’s important to stick to the UK Chief Medical Officers' low risk drinking guidelines. That means no more than 14 units a week, spread over three or more days, with several drink-free days - and no bingeing.

Regularly drinking more than the low risk drinking guidelines increases your risk of serious health conditions including heart problems, high blood pressure  and poor mental health.

Drinking alcohol also causes at least seven types of cancer, including breast, bowel, mouth and throat cancers.² The risk of developing these types of cancer starts to increase even at low levels of drinking - so the less you drink, the more you reduce your risk.

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How much alcohol is in whisky?

Checking a whisky’s ABV (alcohol by volume) tells you what percentage of the drink is made up of alcohol. The higher the percentage, the more alcohol there is - for example, half of a 50% ABV whisky is pure alcohol.

A good way to keep track of how much you’re drinking is to know how many units of alcohol are in your drink. One unit of alcohol is 10ml (ten millilitres) of pure alcohol – and the number of units you are drinking depends on the drink’s size and strength.

Drinking more than 14 single measures of whisky in a week would mean you are drinking more than the UK low risk drinking guidelines.

What is an alcohol unit?

Pubs and bars used to commonly serve spirits like whisky in 25ml measures - that’s about one unit of alcohol per measure of whisky. But these days many pubs and bars have switched to 35ml or 50ml measures – meaning you might be having a lot more alcohol without realising.

If you drink whisky as part of a mixed drink or a cocktail, it’s worth remembering there can be several measures – even if the drink doesn’t taste particularly strong. And if you drink at home, a good way to avoid accidentally pouring too much and limit how many units of alcohol you have is by using a measuring cup.

Buy a measuring cup from the Drinkaware shop

How many calories are there in whisky?

Alcohol contains around seven calories a gram, almost as many as pure fat. So, because whisky contains a lot of alcohol, it’s high in calories too. A typical 25ml single of whisky can contain 61 calories.

As well as having a high calorie content on its own, if you mix whisky with a sugary mixer like lemonade or ginger beer, you could end up drinking far more calories than you realise.

Use our Unit and Calorie Calculator to see what's really in your drink