BAC Calculator UK – Blood Alcohol Limit and Drink-Driving Risks

Understand your estimated BAC and how it relates to drink-driving limits in the UK—but never use any calculator to decide if you can drive.

Estimate your BAC

Enter your details and drinks to see an approximate blood alcohol concentration. Results are only estimates and must not be used to decide if you can drive.

Use an approximate value if you are not sure. The estimate is sensitive to body weight.

This helps us compare your estimated BAC with commonly cited legal limits in your selected region.

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minutes

Count from the first sip of your first drink. The longer you have been drinking, the lower your BAC may be from metabolism.

Drinks you have consumed

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Never use BAC estimates to decide whether you can drive.

Estimated BAC and safety overview

These numbers are only rough estimates. Everyone processes alcohol differently.

Fill in your details and drinks, then select “Estimate BAC” to see estimated values and safety guidance.

Drink-driving limits and enforcement policies in the United Kingdom can change. This page gives a rough overview based on commonly cited values, but you must always consult official government sources for current limits.

Safety first in the United Kingdom

Legal limits are not safety guarantees. You can be too impaired to drive safely even below a legal threshold. Treat this calculator as an educational tool only and choose the safest option available.

Drink-driving questions for the United Kingdom

Drink-driving limits and enforcement policies in the United Kingdom can change. This page gives a rough overview based on commonly cited values, but you must always consult official government sources for current limits.
Many regions apply lower or even zero limits to novice, young, or professional drivers. If you fall into any special category, check the exact rules that apply to you in the United Kingdom.
Regardless of the legal limit in the United Kingdom, the safest option after drinking is always to avoid driving yourself. Arrange a taxi, rideshare, public transport, or a sober driver.

Switch country

View BAC estimates and drink-driving information for other regions: