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Alcohol units calculator

If you've drunk any alcohol, the safest bet is not drive at all.

But you can work out how many units your drinks contain with our alcohol units calculator*:

What's a unit?

It's the measure of the amount of alcohol in a drink. One alcohol unit is measured as 10ml or 8g of pure alcohol.

A typical pint contains around one to two units, and a glass of wine can be between one and a half to three units, depending on the strength and the size of the glass.

Know your limits

Factors like your weight, sex and how much you've eaten, all contribute to how your body responds to alcohol, so it'll affect everyone differently.

After a drink or two, you might think you're fine to drive but even small amounts of alcohol can set you over the limit, so it's better to be safe than sorry and stay out of the car.

In England and Wales, the drink-drive alcohol limit for drivers is:

  • 80mg of alcohol per 100ml of blood
  • 107mg of alcohol per 100ml of urine
  • 35 microgrammes of alcohol per 100ml of breath

In Scotland, the drink-drive alcohol limit has been reduced to:

  • 50mg of alcohol per 100ml of blood
  • 67mg of alcohol per 100ml of urine
  • 22 microgrammes of alcohol per 100ml of breath

Despite this guidance, there's no foolproof way of drinking and staying under the limit because alcohol affects each individual differently.

*The Alcohol Unit Calculator is intended as a rough guide only, and is NOT a substitute for common sense. None for the road is the best approach.


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