FAQ | BAC Calculator

Almost. 49 states and Washington, D.C. set the limit at 0.08% BAC — you are DUI per se at or above that level. Utah is the strictest at 0.05%, the lowest in the nation. Three rules apply everywhere, whatever the state:

• Commercial drivers (CDL): 0.04% BAC, set federally by the FMCSA.
• Drivers under 21: zero tolerance — any measurable alcohol, usually 0.01–0.02%, is an offense.
• High-BAC / aggravated DUI: many states add tougher penalties at around 0.15% BAC.

Fines, jail, license suspension and ignition-interlock rules vary widely by state. See our state guides for California, Texas, Florida, New York and Utah.

The body eliminates alcohol at a remarkably steady rate of about 0.015% BAC per hour — roughly one standard drink per hour. This is set by how quickly your liver metabolizes alcohol and, according to the NIAAA and NHTSA, it cannot be sped up by coffee, water, food, exercise or a cold shower.

In practice, someone at the 0.08% legal limit needs about 5–6 hours to return to 0.00%, and a person at 0.15% needs roughly 10 hours. Individual rates vary a little (about 0.012–0.020% per hour) with body weight, sex, food and liver health, but no trick makes alcohol leave your system faster — only time does.

In the United States, Breathalyzer measurement units are typically expressed as Blood Alcohol Concentration (BAC), which represents the amount of alcohol in a person's bloodstream. The most common unit used is:

This is equivalent to percentage BAC, where a BAC of 0.08 means there are 0.08 grams of alcohol per 100 milliliters of blood (or 0.08%).

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).

The effects of alcohol vary based on body mass, gender, food intake, and overall health. On average, it takes 3 hours to process alcohol equivalent to 500 ml of beer (5%), 50 ml of vodka, or 200 ml of wine (12%).

The most popular breathalyzer in the U.S. appears to be the BACtrack S80 Professional Breathalyzer, which is widely regarded for its police-grade accuracy and reliability. It employs advanced fuel cell sensor technology, making it a top choice for law enforcement, health professionals, and personal use by those who require dependable BAC results.

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.

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.

According to the WHO, a standard alcohol unit (SAV) contains 8g or 10ml (1cl) of pure alcohol. It can be calculated as: alcohol volume (ml) x strength (%) x density (≈0.8g/l) / 10g. For example, 500ml of 5% beer equals 2 SAVs, 750ml of 12% wine equals 7 SAVs, and 500ml of 40% spirits equals 16 SAVs.

How long alcohol stays detectable depends heavily on the test, and it is usually far longer than you feel the effects:

• Breath & blood: up to about 12–24 hours.
• Saliva: roughly 12–24 hours.
• Urine: alcohol itself about 12 hours, but the EtG marker up to 3–4 days.
• Hair: patterns of regular drinking can show up for as long as 90 days.

These longer windows matter mainly for workplace testing, probation, and court-ordered abstinence monitoring. For driving, though, only your current BAC counts — and that comes down solely with time.

Alcohol sales hours in the United States are regulated at the state—and often local—level, leading to significant variation across the country. Below is a general overview of alcohol sales times in several key states:

• California: Alcohol can be sold at retail stores from 6 a.m. to 2 a.m. daily. Bars and restaurants may serve alcohol during the same hours.
• Texas: Retail alcohol sales are permitted from 7 a.m. to midnight, Monday through Friday, and from 7 a.m. to 1 a.m. on Saturday. On Sundays, sales begin at 10 a.m. in stores and noon in bars and restaurants, ending at midnight or 2 a.m. depending on local ordinances.
• New York: Alcohol may be sold in stores from 8 a.m. to midnight, Monday through Saturday, and from noon to 9 p.m. on Sundays. Bars and restaurants can serve alcohol from 8 a.m. to 4 a.m.
• Florida: Alcohol sales are generally allowed from 7 a.m. to midnight, but some counties and cities permit sales until 2 a.m. or later. Sunday sales may have restricted hours.
• Illinois: Most areas allow alcohol sales from 7 a.m. to 2 a.m., with some cities (like Chicago) permitting sales until 3 a.m. or later. Sunday hours may be more limited.
• Georgia: Alcohol sales hours vary widely by county. Many areas allow sales from 7 a.m. to 11:45 p.m. Monday through Saturday, while Sunday sales may start as late as 12:30 p.m.
• Pennsylvania: State-run stores typically operate from 9 a.m. to 10 p.m. Monday through Saturday, and from 11 a.m. to 7 p.m. on Sundays. Bars can serve alcohol until 2 a.m.
• Massachusetts: Retail alcohol sales are allowed from 8 a.m. to 11 p.m. Monday through Saturday, and from 10 a.m. to 11 p.m. on Sundays. Bars may serve until 2 a.m.
• Ohio: Alcohol can be sold in stores from 5:30 a.m. to 1 a.m. Bars and restaurants may serve until 2:30 a.m.
• Louisiana: Sales hours vary by parish, but many areas allow 24-hour sales. New Orleans, for example, permits alcohol sales around the clock.
• Washington: Beer, wine, and spirits can be sold in grocery and retail stores from 6 a.m. to 2 a.m. daily (spirits have been sold in ordinary stores since the 2012 privatization of liquor sales). Bars and restaurants may serve until 2 a.m.

Note: Local ordinances may further restrict or extend these hours. Holidays and special events can also impact when alcohol can be sold or served. Always check local laws for the most accurate information.

Alcohol is broken down in the liver by enzymes. Excessive consumption can lead to fatty liver disease, hepatitis, or even cirrhosis. These conditions can be irreversible, emphasizing the importance of moderation.

Long-term alcohol use can cause health problems like heart disease, high blood pressure, neurological issues, and mental health disorders like depression. It also increases the risk of cancers such as liver and esophageal cancer.

Blood Alcohol Concentration (BAC) impacts behavior and cognitive functions. Lower BAC levels (0.02%-0.05%) cause mild relaxation, while high BAC levels (above 0.08%) impair motor skills, judgment, and increase the risk of aggression.

While alcohol may make you feel relaxed in the moment — it is a central-nervous-system depressant — that effect is short-lived. Within a few hours, as the body processes the alcohol, it releases more stress hormones (cortisol and adrenaline), so anxiety and restlessness can actually rise afterward.

Alcohol also disrupts deep sleep, which lowers your resilience to stress the next day. Using it regularly as a “stress reliever” tends to create a vicious cycle — more drinking, less natural stress tolerance, and a higher risk of anxiety and depression — and can lead to dependence. More effective ways to handle stress include exercise, good sleep habits, breathing techniques, and professional support when the pressure is ongoing.

Recognizing a drinking problem is not always easy, because it usually develops gradually. Common warning signs include frequent urges to drink, loss of control once you start, drinking to improve your mood or escape problems, memory gaps (“blackouts”), and needing more alcohol to feel the same effect.

Another clear sign is continuing to drink despite the consequences — on your health, relationships, or work — or feeling guilty and making failed attempts to cut back. If several of these sound familiar, it is worth seeking professional help. In the U.S., resources such as the SAMHSA National Helpline (1-800-662-HELP), your doctor, or support groups offer free, confidential assistance. Reaching out early is the most effective step.