We use cookies to improve your experience.

US

Blood Alcohol Calculator – BAC Level Over Time 🇺🇸

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.

0.08% BAC Legal limit

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

Try AI Calculator FAQ
  • Instant BAC estimate
  • Sobriety timeline
  • Legal limits for 40+ countries
Drunk driving in the United States — 0.08% BAC

The 0.08% per se limit applies in every state except Utah (0.05%). Commercial driver license holders are limited to 0.04% while operating a commercial vehicle. Under-21 drivers are subject to state Zero Tolerance laws — most set 0.00% or 0.02%.

ℹ️ Information

CONTEXT
🌎 Country
Show results in
🏛️ State
  • All states (federal 0.08%)
  • California
  • Texas
  • Florida
  • New York
  • Utah
ABOUT YOU
Sex
⚖️ Weight

lbs

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

🕒

⏳ Or: hours ago —
0h6h12h18h24h

🍹🍸🍺 Drinks

Drink {{ index+1 }}

{{ drinkSummary(drink) }}

%

≈ {{ servingHint(drink) }}

Maximum number of drinks reached.

The results will show up here...
📈 Results
Current BACPeak BAC {{ initialSobriety }}{{ unitSign }} Legal limit {{ countryLimit }}{{ unitSign }}
Safe Caution Impaired Intoxicated Dangerous
Above the legal limit – do not drive. Close to the legal limit – driving not recommended. Safe to drive, but stay cautious.
{{ legalLimitTimeLabel }}
Sober in: {{ sobrietyTime }}

Drunk driving in the United States

Drivers 21 and over 0.08%
Commercial drivers (CDL) 0.04%
Drivers under 21 0.00–0.02%

Common Penalties in the United States

Offence type No offence Below the legal limit – driving is permitted.
Offence type Over the 0.0 limit Zero-tolerance country — driving with any detectable alcohol is prohibited.
Offence type Over the legal limit You are over the legal limit and committing a drink-driving offence. Exact penalties depend on your BAC and local law.
Offence type DUI / DWI (per se) 0.08% – 0.14% BAC Criminal DUI/DWI offence — a misdemeanor on a first offense in most states.
Typical penalties
  • Per se DUI — fine $500–$2,000+ (first offense)
  • License suspension 90 days – 1 year
  • Up to 6 months jail; ignition interlock common
Offence type High-BAC / aggravated DUI 0.15%+ BAC Criminal offence — may result in a criminal record.
Typical penalties
  • High BAC / aggravated DUI — enhanced fines, often $1,000–$2,500+
  • Multi-year suspension possible
  • Felony exposure with priors or injury
These are general penalties. Actual consequences may vary by local law and circumstances. Learn more →

Legal limit

{{ countryLimit }}{{ unitSign }}
Based on US law ·

Elimination rate

{{ decayRateDisplay }}{{ unitSign }} / h
Assumed average

Standard Drinks

{{ standardDrinks }}🍺
Approx. consumed

Pure Alcohol

{{ results.length > 0 ? results[0].pureAlcoholMl : '0' }} {{ qunits }}
Pure alcohol consumed

Pure Alcohol (g)

{{ alcoholGrams }} g
Total ethanol consumed

Calories

{{ calories }} kcal
From alcohol only — mixers add more

Time over limit

{{ timeOverLimit || '0m' }}
Estimated duration above the legal driving limit
For your own safety, we recommend using a rate no higher than the average.
Current BACPeak BAC {{ initialSobriety }}{{ unitSign }} Legal limit {{ countryLimit }}{{ unitSign }}
Safe Caution Impaired Intoxicated Dangerous
Above the legal limit – do not drive. Close to the legal limit – driving not recommended. Safe to drive, but stay cautious.
{{ legalLimitTimeLabel }}
Sober in: {{ sobrietyTime }}

Drunk driving in the United States

Drivers 21 and over 0.08%
Commercial drivers (CDL) 0.04%
Drivers under 21 0.00–0.02%

Common Penalties in the United States

Offence type No offence Below the legal limit – driving is permitted.
Offence type Over the 0.0 limit Zero-tolerance country — driving with any detectable alcohol is prohibited.
Offence type Over the legal limit You are over the legal limit and committing a drink-driving offence. Exact penalties depend on your BAC and local law.
Offence type DUI / DWI (per se) 0.08% – 0.14% BAC Criminal DUI/DWI offence — a misdemeanor on a first offense in most states.
Typical penalties
  • Per se DUI — fine $500–$2,000+ (first offense)
  • License suspension 90 days – 1 year
  • Up to 6 months jail; ignition interlock common
Offence type High-BAC / aggravated DUI 0.15%+ BAC Criminal offence — may result in a criminal record.
Typical penalties
  • High BAC / aggravated DUI — enhanced fines, often $1,000–$2,500+
  • Multi-year suspension possible
  • Felony exposure with priors or injury
These are general penalties. Actual consequences may vary by local law and circumstances. Learn more →
{{ afterLabel }} {{ $t('unit.' + units) }} Status
{{ result.time }} {{ result.drunkenness }}
  • Safe to drive, but stay cautious.
  • Close to the legal limit – driving not recommended.
  • Above the legal limit – do not drive.
Create a pop-up notification

Sobriety Over Time

Your estimated BAC as your body clears the alcohol

Sober in {{ sobrietyTime }}
  • {{ lookaheadBacDisplay }}{{ unitSign }} Above the legal limit – do not drive. Close to the legal limit – driving not recommended. Safe to drive, but stay cautious.
  • {{ $t('unit.' + units) }}
  • Legal limit ({{ countryLimit }}{{ unitSign }})
👮 Health impact and legal consequences
{{ item.title }}
Peak BAC: {{ peakBAC }}

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

To the top ⬆️

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

About results
Current BAC

Your Current BAC is the estimated percentage of alcohol in your bloodstream right now — 0.08 % means 0.08 grams of alcohol per 100 milliliters of blood. It is the same figure a police breathalyzer or blood draw reports, and the number every state writes its DUI law around.

Legal limit

The per se limit is 0.08 % BAC in every state except Utah, which lowered its limit to 0.05 % in 2018. Commercial drivers are held to 0.04 %, and every state enforces Zero Tolerance laws for drivers under 21 (usually 0.00–0.02 %). At or above the per se limit you can be convicted on the number alone, and refusing a breath test triggers an automatic license suspension under your state’s implied-consent law.

Elimination rate

The average rate your liver clears alcohol — about 0.015 % BAC per hour, or roughly one standard drink an hour. It varies with your body and metabolism, and nothing on the internet speeds it up: coffee, a cold shower or a big meal change how you feel, not how fast your BAC actually falls.

Standard Drinks

A U.S. standard drink (NIAAA) is 0.6 fl oz (14 g) of pure alcohol — a 12 oz beer at 5 %, a 5 oz glass of wine at 12 %, or a 1.5 oz shot of 80-proof spirits. This total converts your drinks into standard-drink units, because a heavy craft beer or a generous pour can count as two.

Pure Alcohol

The amount of pure alcohol (in ounces) your body has absorbed so far — the raw figure your standard-drink count and BAC are both built from.

Time vs. Sobriety Table

The table projects how your BAC changes each hour — and when you enter a start time of drinking, it maps those estimates onto the actual time of day. Start at 8:00 PM and the column reads your projected BAC at 8:00 PM (Now), 9:00 PM (1h), 10:00 PM (2h), and so on, so you can see the clock time you are likely to drop back under 0.08 %. Status icons flag whether each hour is safe to drive, making it easier to plan a ride home or a rest before morning.

Sobriety Over Time Graph

A line chart of your estimated BAC declining over the hours ahead, so you can see at a glance when it drops below the legal limit and below a genuinely safe level.

How Alcohol Affects You

A reference table matching BAC ranges to their typical effects on your body and behavior — from subtle changes in judgment and reaction time to serious impairment at higher levels.

Legal limit reached in / Sober in / Peak BAC

These summaries give the key estimates at a glance:

  • Legal limit reached in: the time until your BAC likely falls below the 0.08 % driving limit.

  • Sober in: total time until your BAC returns to ~0.000 %.

  • Peak BAC: the highest BAC value reached during the session.

Data used for calculations

Five factors that determine your result

Weight
Body weight determines how alcohol distributes in the body — more weight means a lower blood alcohol concentration.
Sex
Men and women metabolize alcohol at different rates because of differences in body water content.
Amount
The amount of pure alcohol consumed is the main factor that determines your BAC result.
Strength
A higher strength (%) means more ethanol in the same drink serving.
Time
The time of your first drink shows how BAC changes hour by hour and when you'll be sober again.

How much does United States drink?

Alcohol consumption per adult, per year

9.8L

litres of pure alcohol per adult (15+), per year

Per adult, that is roughly:

552 beers ≈ 11/week
544 glasses of wine ≈ 10/week
613 shots ≈ 12/week
9.8 L
1.7 L Ø 6.0 11.4 L

62% above the regional average

Ranks #3 of 35 in the Americas Ranks #33 of 188 in the World Average in the Americas: 6.0 L

How neighbours compare

#1 Canada 10.0L #2 the Americas
#2 United States 9.8L #3 the Americas
#3 Bahamas 6.9L #12 the Americas
#4 Mexico 6.0L #18 the Americas
#5 Cuba 5.6L #20 the Americas

How safe are the roads in United States?

Road traffic deaths per 100,000 people, per year

14.2 /100k

road traffic deaths per 100,000 people, 2021

~39% of road deaths linked to alcohol WHO estimate, 2019 · 27–53%
918 road deaths per week WHO estimate, 2021
355 alcohol-linked deaths per week WHO-derived estimate
14.2
4.7 Ø 14.1 31.3

1% more road deaths than the regional average

#20 safest of 36 in the Americas #117 safest of 195 worldwide Average in the Americas: 14.1 per 100k

How neighbours compare

#1 Canada 4.7 #1 the Americas
#2 Cuba 5.4 #4 the Americas
#3 Mexico 12.0 #13 the Americas
#4 United States 14.2 #20 the Americas
#5 Bahamas 16.2 #24 the Americas

Latest available year shown per country.

LIMITS NEARBY

BAC limits in neighboring countries

Explore the legal blood alcohol concentration (BAC) limits for drivers in nearby countries.

CA

Canada

0.08%
Relaxed
MX

Mexico

0.04%
Strict
CU

Cuba

0.05%
Moderate
BS

Bahamas

0.08%
Relaxed

Drunk driving in the United States

Legal BAC limits for drivers in the United States

Drivers 21 and over
0.08%
Relaxed
Commercial drivers (CDL)
0.04%
Strict
Drivers under 21
0.00–0.02%
Zero tolerance
The 0.08% per se limit applies in every state except Utah (0.05%). Commercial driver license holders are limited to 0.04% while operating a commercial vehicle. Under-21 drivers are subject to state Zero Tolerance laws — most set 0.00% or 0.02%.

Common Penalties in the United States

Consequences of exceeding the legal BAC limit

0.08% – 0.14% BAC
DUI / DWI (per se)
  • Per se DUI — fine $500–$2,000+ (first offense)
  • License suspension 90 days – 1 year
  • Up to 6 months jail; ignition interlock common
0.15%+ BAC
High-BAC / aggravated DUI
  • High BAC / aggravated DUI — enhanced fines, often $1,000–$2,500+
  • Multi-year suspension possible
  • Felony exposure with priors or injury

Tips for Responsible Drinking

Practical tips for safer drinking

Pace yourself
Stick to the "one drink per hour" rule – your liver needs time to process alcohol.
Eat before and while drinking
A solid meal slows alcohol absorption – an empty stomach raises BAC faster.
Drink water
After each alcoholic drink, have a glass of water – it reduces dehydration and health risks.
Don't drive
Even small amounts of alcohol impair reaction time. If in doubt, call a taxi or stay overnight.

Source: World Health Organization (WHO).

Official sources & references

The limits and penalties on this page come from official government sources

Confirm the current rules directly with the responsible authorities:

Laws change — always check the latest limits and penalties with the official source before driving.

How we calculate your BAC

The exact formula, step by step

Your result is not a guess. It comes from the Widmark equation, the same formula forensic toxicologists use in court. Here it is, worked through with an example.

BAC = A ÷ (r × W) − (β × t)

where A = grams of pure alcohol, r = body-water factor (0.68 for men, 0.55 for women), W = weight in kg, β = elimination rate (~0.15 g/L per hour), and t = hours since your first drink.

  1. Pure alcohol (A). Three 500 ml beers at 5% ABV hold 3 × 500 × 0.05 × 0.789 ≈ 59 g of pure alcohol.
  2. Body water (r × W). For an 80 kg man: 0.68 × 80 = 54.4.
  3. Peak level. A ÷ (r × W) = 59 ÷ 54.4 ≈ 1.09 g/L — the same as 1.09‰ or about 0.11% BAC.
  4. Subtract elimination. After 2 hours: 1.09 − (0.15 × 2) = 0.79 g/L.

The calculator runs this same equation on your own weight, sex, drinks and timing — the numbers above are only a worked example. Method based on E. M. P. Widmark (1932); results are an estimate, not a legal measurement.

What people actually log

SmartBAC has run over 17,000 calculations in recent weeks. Of every drink people log, beer is the most common by far — about 6 in 10 — ahead of spirits and then wine.

Anonymous, aggregated first-party usage data from SmartBAC, July–August 2026.

FAQ

How long does it take for a BAC of 0.1% to leave the body?

The body eliminates alcohol slowly and at a fairly steady rate — roughly 0.012–0.020% BAC per hour, handled almost entirely by the liver. Based on that rate, it typically takes 5 to 8 hours to clear 0.1% BAC, depending on the individual.

The exact speed depends on body weight, sex, liver health, food, and how much you drank, but the rate cannot be sped up — coffee, a cold shower, exercise, or a big meal make no difference. Only time lowers your BAC. This is why residual alcohol the next morning is a common cause of DUI arrests: someone who ends the night at 0.15% can still be over the 0.08% legal limit hours later. Use the calculator as an estimate and always add a safety margin before driving.

How can I sober up faster?

No — the idea that you can sober up faster is a persistent myth. Alcohol is broken down almost entirely by the liver, at a fixed rate of about 0.015% BAC per hour, and nothing speeds that up. Drinking water, coffee, a cold shower, exercise, or a big meal do not lower your blood alcohol concentration.

Water is still worth drinking — it helps with the dehydration behind many hangover symptoms, so you may feel a bit better — but it does not reduce your BAC or make you safe to drive. Coffee can make you feel more alert while you are still legally impaired, which is arguably more dangerous. The only thing that actually lowers your BAC is time. If you have been drinking, plan enough hours before driving, or do not drive at all.

What is the margin of error for breathalyzers?

In the United States, breathalyzer devices are not 100% accurate and are allowed a certain error margin or tolerance range. The specific error margin can vary depending on the state, the type of device, and whether the test is being used for evidentiary purposes (e.g., in court) or as a preliminary roadside screening. But most breathalyzers used by law enforcement are required to have an accuracy of ±0.005 g/210L or ±0.01 g/210L at the legal limit (0.08% BAC).

Read all

FAQs 15 FAQs

Read all

Articles 19 related articles

Read all