Blood Alcohol Content (BAC) Calculator 🇺🇸

Calculate your estimated Blood Alcohol Concentration (BAC) instantly. Track standard drinks, view sobriety charts, and check your status against the 0.08% US legal limit.

Do you fancy AI? Try our AI-powered BAC calculator.

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ℹ️ Information

CONTEXT
🌎 Country
Show results in
ABOUT YOU
Sex
Weight

Start time of drinking (optional) Time of your first drink (not required)

🕒

🍹🍸🍺 Drinks

Drink {{index+1}} 🍷

🍺 🍷 🥃 🍺 🍹 Standard cocktail usually contains single shot of hard liquor. 🥂
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%

The results will show up here...
📈 Results

Current BAC

{{ initialSobriety }}{{ unitSign }}
Measured for Now

Legal limit

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Based on US law

Elimination rate

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Assumed average

Standard Drinks

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Approx. consumed

Pure Alcohol

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Pure alcohol consumed
For your own safety, we recommend using a rate no higher than the average.
🟢 Status indicators
🔴 Above the legal limit – do not drive.
🟡 Close to the legal limit – driving not recommended.
🟢 Safe to drive, but stay cautious.
{{ afterLabel }} {{ $t('unit.' + units) }} Status
{{ result.time }} {{ result.drunkenness }} {{ result.statusLabel }}
Create a pop-up notification
📉 Sobriety Over Time
👮 Health impact and legal consequences
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Legal limit reached in: {{ legalLimitTimeLabel }} Sober in: {{ sobrietyTime }} Peak BAC: {{ peakBAC }}

💡 Tips: drink water, eat, and avoid driving until below the legal limit and ideally sober.

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Attention‼️ The results are only approximate, so make sure you are sober before driving.

About results ▼

📊 Current BAC

Your Current BAC shows your estimated blood alcohol concentration right now as a percentage. This number reflects how much alcohol is in your bloodstream and is used to assess impairment.

🚔 Legal limit

In the United States and Canada, the standard legal driving limit for fully licensed adults is 0.08 % BAC. Exceeding this can result in DUI/DWI penalties, including fines and license actions.

🧪 Elimination rate

This shows the assumed average rate your body metabolizes alcohol — typically ~0.015 % BAC per hour. It’s an estimate of how fast your BAC decreases over time.

🍺 Standard Drinks

The number of Standard Drinks represents the approximate number of typical servings you’ve consumed (e.g., one beer, glass of wine, or shot), based on local standards for drink size.

🧴 Pure Alcohol

This is the amount of pure alcohol (in ounces) your body has absorbed so far, giving you a measure of total alcohol consumed.

⏱ Time vs. Sobriety Table

The table lists how your BAC is expected to change with each hour passed — and when a Start time of drinking is provided, it aligns these estimates with the exact time of day you began drinking. For example, if you started at 6:00 PM, the column will show your projected BAC at 6:00 PM (Now), 7:00 PM (1h), 8:00 PM (2h), etc., so you can clearly see when your BAC is likely to cross legal and safer thresholds as the day progresses. Icons or status indicators show whether the level is safe for driving at those specific clock times, making it easier to plan your departure or rest period.

📈 Sobriety Over Time Graph

A visual line chart plotting your estimated BAC decline over hours. It helps you see when your BAC drops below legal and safer levels.

😵 How Alcohol Affects You

This reference table shows ranges of BAC and typical effects on your body and behaviour — from mild alertness changes to significant impairment at higher levels.

⏰ Legal limit reached in / Sober in / Peak BAC

These summaries give quick key estimates:

  • Legal limit reached in: the time until your BAC likely falls below the legal driving limit.

  • Sober in: total time until BAC reaches ~0.000 %.

  • Peak BAC: the highest BAC value recorded in the session.

Data used for calculations

In order to accurately calculate the effects of alcohol on the body, the following important data are required:

  1. Weight (kg):: Body mass has a direct impact on the absorption of alcohol. Higher weight determines a slower effect of alcohol on the body.
  2. Gender: The bodies of women and men process alcohol differently. Alcohol is broken down more slowly in women's bodies due to a lower amount of enzymes that break down alcohol.
  3. Amount of alcohol consumed (ml): It is necessary to indicate the exact volume of the alcoholic drink consumed in milliliters.
  4. Alcoholic strength (%): This indicator shows the concentration of ethanol in the drink. It is an important factor in determining the total amount of pure alcohol consumed.
  5. The 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.

These data are essential for accurately calculating the effects of alcohol on the body and assessing its impact on different individuals.

Drunk driving in the United States

For drivers 21 years or older:

  • Driving with a blood alcohol concentration (BAC) of 0.08% or higher is illegal.

For drivers under 21 years old:

  • The legal limit is lower, with state limits ranging from 0.00 to 0.02.

Common Penalties in the United States

  1. Fines
    • Ranges: $100 to $10,000, depending on the state and the offense (first, second, or subsequent).
  2. License Suspension
    • First offense: 30 days to 1 year.
    • Repeat offenses: Up to several years or permanent revocation in severe cases.
  3. Jail Time
    • First offense: No jail or up to 6 months.
    • Repeat or aggravated offenses: 1 year or more.
  4. Community Service
    • Mandatory hours in many states.
  5. Alcohol Education or Treatment Programs
    • Often required for first-time offenders to regain driving privileges.
  6. Ignition Interlock Devices (IID)
    • Installed in vehicles to prevent operation if alcohol is detected on the driver’s breath.
    • Frequently mandatory for repeat offenders or cases involving high blood alcohol concentration (BAC).

Tips for Responsible Drinking

  • Limit your alcohol consumption – follow the “one drink per hour” rule.
  • Consume alcohol with meals to slow down its absorption.
  • Drink a glass of water after each alcoholic drink.
  • Do not drive after consuming even a small amount of alcohol.

Source: World Health Organization (WHO).

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