Alcohol unit calculator

The amount of alcohol in a drink is measured in 'units'. One unit refers to 10ml of alcohol.

It is recommended to avoid alcohol completely in pregnancy, particularly during the first three months as this is the time of greatest development for your child. 

Alcohol unit calculator

The more units in a drink, the stronger it is. The percent numbers (%) you see on the label of the bottle or can will tell you how much of the drink is pure alcohol.

Examples of one unit of alcohol are:

  • half a pint (284ml) of beer, lager or cider that is under 4% alcohol volume (lots are more than this so check the bottle or ask in the pub)
  • a quarter of a pint (142ml) of stronger beer, lager or cider
  • one glass of wine (125ml) that is under 9% alcohol volume - most wine is served in glasses that take either 175ml or 250ml and the alcohol content is more often 11% to 14% so a glass will usually contain at least two units
  • one single (pub) measure of spirits (25ml) - this is based on drinks that are lower than 40% alcohol volume
  • one small glass of sherry (50ml) of under 20% alcohol volume
  • half an alcopop that is under 4% alcohol volume - many are more than this so it's important to check.

Most women choose to give alcohol up completely as this is the safest course of action for their baby.

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    Last reviewed on June 27th, 2017. Next review date June 27th, 2020.

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    Please note that these comments are monitored but not answered by Tommy’s. Please call your GP or maternity unit if you have concerns about your health or your baby’s health.

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