0.01 - 0.05%
Level
Sober / Minimal
Typical Effects
Slight relaxation and mild mood lift. Reaction time is largely unaffected. Below legal limits in all jurisdictions.
Blood Alcohol Content Tool
BAC Calculator: Know Your Blood Alcohol Content Before You Drive
Free BAC Calculator for 22 countries. Estimate blood alcohol content by drinks, weight, and time. Compare your BAC against local legal limits instantly.
Food, medication, genetics, and tolerance can all change your real BAC estimate.
Use Responsibly
This BAC Calculator is an estimate, not a breathalyzer or medical test.
Never use a BAC Calculator to decide whether to drive after drinking.
Interactive Tool
How the BAC Calculator Works
Use the full BAC Calculator below to estimate blood alcohol content by country, drink type, body weight, biological sex, and time elapsed. This BAC Calculator applies the Widmark formula so you can compare your estimated BAC against the selected legal limit and see how long alcohol may take to clear.
baccalculator.me - Widmark Formula Engine
Full Calculation Inputs
Choose your country, enter your drink type, add your body weight, and let the BAC Calculator estimate blood alcohol content and compare it with the selected legal limit.
๐บ๐ธUnited StatesยทLegal limit: 0.08%ยทUtah: 0.05%. Zero tolerance under 21.
Education
What Your BAC Level Really Means
Blood alcohol content measures grams of alcohol per deciliter of blood. This BAC Calculator table adds context to the BAC estimate you see after using the calculator.
0.06 - 0.08%
Level
Mildly Impaired
Typical Effects
Reduced inhibition and subtly impaired judgment. Fine motor control begins to decline. At or near the 0.08% US legal limit.
0.09 - 0.15%
Level
Impaired
Typical Effects
Noticeable balance, coordination, and reaction impairment. Slurred speech and memory gaps become more common.
0.16 - 0.25%
Level
Severely Impaired
Typical Effects
Major loss of coordination and balance. Nausea and disorientation are common. Blackout risk rises sharply.
0.26%+
Level
Potentially Fatal
Typical Effects
Risk of alcohol poisoning, loss of consciousness, and respiratory suppression. Seek emergency medical attention immediately.
| BAC Range | Level | Typical Effects |
|---|---|---|
| 0.01 - 0.05% | Sober / Minimal | Slight relaxation and mild mood lift. Reaction time is largely unaffected. Below legal limits in all jurisdictions. |
| 0.06 - 0.08% | Mildly Impaired | Reduced inhibition and subtly impaired judgment. Fine motor control begins to decline. At or near the 0.08% US legal limit. |
| 0.09 - 0.15% | Impaired | Noticeable balance, coordination, and reaction impairment. Slurred speech and memory gaps become more common. |
| 0.16 - 0.25% | Severely Impaired | Major loss of coordination and balance. Nausea and disorientation are common. Blackout risk rises sharply. |
| 0.26%+ | Potentially Fatal | Risk of alcohol poisoning, loss of consciousness, and respiratory suppression. Seek emergency medical attention immediately. |
Science
Factors That Affect Your BAC
No two people metabolize alcohol identically. This BAC Calculator uses the Widmark formula, but real-world BAC outcomes still depend on several personal factors.
01
Body Weight
Heavier individuals have a larger volume of body fluids, which dilutes alcohol more efficiently than in lighter individuals.
02
Biological Sex
Differences in body composition and alcohol dehydrogenase levels can change how alcohol distributes through the body.
03
Time Elapsed
Your liver metabolizes alcohol over time, usually around 0.015% BAC per hour on average.
04
Food Intake
Eating before or during drinking slows absorption, which can reduce and delay peak BAC.
05
Medications
Prescription and over-the-counter drugs can amplify impairment or change how your body responds to alcohol.
06
Genetics & Tolerance
Genetic variation changes metabolism speed. Tolerance can affect how impaired you feel, but not your actual BAC.
Legal Reference
Legal BAC Limits by State and Country
The legal BAC limit for driving varies by jurisdiction and driver category. This BAC Calculator compares your BAC estimate with common thresholds, but a legal BAC does not mean you are safe to drive.
United States
Most States
0.08%
Standard federal guideline
Utah
0.05%
Strictest in the US
Under 21
0.00%
Zero tolerance laws
CDL Drivers
0.04%
Commercial vehicle operators
International
| Country | Legal Limit | Notes |
|---|---|---|
| ๐บ๐ธUnited States | 0.080% | Utah: 0.05%. Zero tolerance under 21. |
| ๐ฌ๐งUK (England & Wales) | 0.080% | Separate threshold from Scotland. |
| ๐ฌ๐งUK (Scotland) | 0.050% | Lower limit than England and Wales. |
| ๐จ๐ฆCanada | 0.080% | Warning range starts at 0.05%. |
| ๐ฆ๐บAustralia | 0.050% | 0.00% for probationary drivers. |
| ๐ฉ๐ชGermany | 0.050% | Lower threshold for some drivers. |
| ๐ซ๐ทFrance | 0.050% | Often stricter for novice drivers. |
| ๐ฏ๐ตJapan | 0.030% | Strict enforcement; near zero tolerance. |
| ๐จ๐ณChina | 0.020% | Drunk driving threshold is higher, but this is the drink-driving line. |
| ๐ธ๐ชSweden | 0.020% | Among the strictest in Europe. |
| ๐ง๐ทBrazil | Zero Tolerance | Zero tolerance policy. |
| ๐ญ๐บHungary | Zero Tolerance | Zero tolerance policy. |
| ๐จ๐ฟCzech Republic | Zero Tolerance | Zero tolerance policy. |
| ๐ฎ๐ณIndia | 0.030% | Threshold varies in enforcement by state, but 0.03% is commonly cited. |
| ๐ฒ๐ฝMexico | 0.080% | Local enforcement can vary. |
| ๐ณ๐ฟNew Zealand | 0.050% | Lower alcohol-breath limit rules also apply. |
| ๐ฟ๐ฆSouth Africa | 0.050% | Professional drivers may face stricter rules. |
| ๐ฐ๐ทSouth Korea | 0.030% | Penalties escalate quickly above the threshold. |
| ๐ธ๐ฌSingapore | 0.080% | Severe penalties and strict enforcement. |
| ๐ณ๐ดNorway | 0.020% | Very strict threshold. |
| ๐ต๐ฑPoland | 0.020% | Very strict threshold. |
| ๐ท๐บRussia | 0.035% | Often represented as 0.035%. |
โ Zero toleranceโ <= 0.02%โ <= 0.05%โ 0.08%
Always verify the current legal BAC limit with your local authority before driving. Laws can change and often vary by age, license type, and prior offenses.
Method
Why This BAC Calculator Uses These Inputs
This BAC Calculator explains its estimate through standard drink conversion, Widmark formula modeling, and the commonly cited average metabolism rate used in educational tools.
Widmark Formula
This BAC Calculator uses the Widmark formula because it remains one of the most widely recognized methods for estimating blood alcohol content. In practical form, the formula is BAC = (A / (W x r)) x 100 - (0.015 x T), where A is pure alcohol in grams, W is body weight in grams, r is the body-water distribution constant, and T is hours elapsed. The r value is commonly modeled as 0.68 for males and 0.55 for females to reflect average alcohol distribution differences. Erik Widmark developed this approach in the 1930s, and it still underpins many forensic and educational blood alcohol content calculations.
Standard Drink Conversion
A BAC Calculator is only as useful as its drink assumptions, so drink type matters. One standard US drink contains about 0.6 fluid ounces or 14 grams of pure alcohol, which is roughly a 12 oz beer at 5% ABV, a 5 oz glass of wine at 12% ABV, or a 1.5 oz pour of 40% spirits. Strong beer can contain substantially more alcohol than regular beer, which is why a strong beer entry in the BAC Calculator can produce a noticeably higher blood alcohol content estimate from the same drink count.
Average Metabolism Rate
This BAC Calculator applies the commonly cited average decline rate of about 0.015% BAC per hour to estimate how long alcohol may take to clear. Real metabolism can vary meaningfully, and published ranges often fall closer to 0.010% to 0.020% BAC per hour depending on liver health, genetics, food, and other biological factors. Coffee, water, exercise, and cold showers do not accelerate alcohol metabolism once alcohol is already in the bloodstream. Only time reduces BAC in a reliable way.
Help
BAC Calculator FAQ
Common questions about this BAC Calculator, blood alcohol content, the Widmark formula, and responsible drinking.
This BAC Calculator uses the Widmark formula, a standard BAC estimation method. It is still only an estimate because food intake, hydration, medications, and metabolism can change real BAC.
The Widmark formula estimates blood alcohol content from alcohol consumed, body weight, a distribution constant, and elapsed time. This BAC Calculator uses that formula because it remains the most common practical model for educational blood alcohol content estimation.
A common average metabolism rate is 0.015% BAC per hour. Coffee, water, and cold showers do not speed this up. Only time lowers BAC.
A standard US drink contains 0.6 fluid ounces or about 14 grams of pure alcohol. That is about one 12 oz beer, one 5 oz glass of wine, or one 1.5 oz shot of spirits.
The Widmark formula uses different distribution constants because body composition and alcohol distribution differ on average between males and females.
Food does not lower BAC already in your bloodstream, but it can slow alcohol absorption and reduce peak BAC.
No. This BAC Calculator is for education only. Never use an app to decide whether to drive after drinking.