To provide an accurate estimate of your blood alcohol content (BAC), our UK-specific alcohol calculator blood model requires the following data:

1. Weight (kg): Your body mass significantly affects how quickly alcohol is absorbed and processed. Generally, higher weight slows down intoxication.
2. Gender: Biological sex affects alcohol metabolism. Women typically have lower alcohol dehydrogenase activity, causing slower alcohol breakdown.
3. Alcohol Volume (ml): The total volume of alcohol consumed helps determine your BAC. Enter the actual liquid amount in millilitres.
4. Alcohol Strength (% ABV): Indicates the ethanol content in the drink. This figure is crucial in calculating pure alcohol consumed.
5. The selected time of the first drink (optional): If you provide the clock time of the first drink, the calculator anchors results to the time of day and shows how sobriety changes across the day — this allows you to see your estimated sobriety for the current clock time. If you do not provide the first-drink time, the calculator presents sobriety relative to the elapsed time (hours passed) since the start of drinking, comparing levels by hours rather than mapping them to specific times of day.

Our system functions as a type of digital alcohol countermeasure system, helping users assess the likely effects of alcohol on their body based on science-backed formulas used in UK law enforcement and healthcare.

England, Wales, and Northern Ireland:

• The legal blood alcohol concentration (BAC) limit is 0.08% (80mg of alcohol per 100ml of blood).
• Breath limit: 35 micrograms of alcohol per 100ml of breath.

Scotland:

• The legal limit is lower at 0.05% (50mg per 100ml of blood) and 22 micrograms per 100ml of breath.

UK police use breathalysers and other alcohol countermeasure systems to detect violations. Exceeding the limit can result in fines, bans, or imprisonment depending on severity and BAC level.

1. Fines
   • Fines can reach up to £5,000 depending on the severity and whether it’s a first or repeat offence.
2. Driving Ban
   • Minimum 12-month disqualification for first offences.
   • Up to several years or permanent disqualification for repeat offences or extremely high blood alcohol content.
3. Imprisonment
   • Up to 6 months for driving over the legal alcohol limit.
   • Up to 14 years if alcohol-impaired driving results in a fatality.
4. Community Orders
   • May include unpaid work, rehabilitation, or alcohol treatment programmes.
5. Alcohol Awareness & Education
   • Rehabilitation courses may reduce driving bans by up to 25%.
   • Part of broader alcohol law enforcement strategies in the UK.
6. High-Risk Offender Scheme
   • Applies to drivers with very high blood alcohol content (BAC).
   • Medical clearance is required before reapplying for a licence.

Source: UK Government, DVLA, and Alcohol Law Enforcement Policies

• Keep within NHS guidelines: no more than 14 units per week spread over 3+ days.
• Watch for alcohol poisoning signs: confusion, vomiting, slow breathing, or unconsciousness – seek emergency help if these occur.
• Never drive after drinking – even a small amount affects your blood alcohol content and driving judgement.
• Drink water between alcoholic beverages to stay hydrated and reduce intoxication risk.
• Eat before and during drinking to slow alcohol absorption.

Source: NHS, Drinkaware, and Public Health England