DriveCheck — BAC Calculator & Legal Limit Checker

No. It’s an estimate using population averages. Only certified breath/blood tests are legally valid. Treat results as informative, not authoritative.

Yes. The Widmark factor (r) accounts for body water differences by sex. Weight changes dilution volume, affecting BAC.

It shortens the absorption delay, so alcohol reaches peak BAC sooner and often slightly higher.

We use ~0.015 BAC/hour as a typical average. Individual metabolism varies with genetics, health, and context.

Beer ~12 oz at 5%, wine ~5 oz at 12%, spirits ~1.5 oz at 40%. You can adjust via Custom for stronger pours.

No. Water and coffee may help how you feel, but they don’t significantly accelerate alcohol elimination.

For long sessions or high intake, BAC may remain above the limit beyond the simulated horizon. In 0.00% regions (e.g., Japan), legal time equals full sobriety.

That indicates the timeline has passed into the next day, helping avoid confusion around midnight rollover.

Real devices measure BrAC with calibrated sensors. This model estimates BAC from inputs and averages; differences are expected.

No. BAC is blood alcohol concentration; BrAC is breath alcohol concentration. They correlate but are not identical.

Yes. Use the Custom option to enter actual volume and ABV (many craft beers exceed 6–7%).

The tool tracks absorption across the boundary and labels times with (+Nd) to clarify next‑day steps.

Some medications and health conditions can change absorption/elimination or increase impairment. Consult a medical professional.

Food slows absorption but doesn’t change how much alcohol you consumed. You can still be over the legal limit.

If your peak is very low or the horizon hasn’t reached 0.00–0.002% yet, the tool may display “N/A” or “more than 12 hours after start.”

Not necessarily. Even low BAC can impair driving. When in doubt, choose a sober ride.

No. It’s an educational tool and not suitable for policy enforcement or legal arguments.

Use the built‑in Copy Results, Export to TXT, or Print/Export buttons below the results panel.

Start times are needed to place absorption on the timeline. Without them, the calculator can’t build the curve.

Yes. Choose Custom from the country list and enter your threshold (e.g., 0.03).

It provides an estimate based on standard formulas and averages. Actual BAC may vary due to factors like health, fatigue, medication, and drinking pace.

On average, the body metabolizes 0.015% BAC per hour. This can vary depending on weight, gender, and health.

It depends on your weight, gender, and how quickly you drank them. For some people, 2 beers can exceed the legal limit in countries like Japan or Norway.

Food slows alcohol absorption but does not speed up BAC reduction — only time does that.

No — mixers may affect how quickly alcohol is absorbed, but BAC is based on the amount of alcohol consumed.

Limits are based on local safety studies, accident statistics, and cultural factors.

It’s legal in some countries, but even small amounts of alcohol can impair reaction times and judgment.

Women generally have a higher BAC than men after consuming the same amount of alcohol due to lower body water percentage and different enzyme activity.

There is no universal safe number of drinks that guarantees you are under the legal limit. Your blood alcohol concentration (BAC) depends on your weight, gender, metabolism, drink strength, and how quickly you drink. In some countries, such as Japan or Brazil, the legal limit is 0.00% — meaning even a small amount of alcohol can put you over the limit. Always check the country-specific BAC laws and consider using a BAC calculator before driving.

The maximum BAC limit for drivers varies by country:

• USA: 0.08% for regular drivers, 0.04% for commercial drivers.
• Germany: 0.05% for experienced drivers, 0.00% for novice and professional drivers.
• UK: 0.08% in England/Wales/Northern Ireland, 0.05% in Scotland.
• Japan: 0.00% (zero tolerance).

In Germany, the general BAC limit is 0.05% (0.5‰). For novice drivers (less than 2 years of experience) and drivers under 21, the limit is 0.00%. Professional drivers, bus drivers, and those transporting passengers are also subject to a 0.00% limit.

On average, the body metabolizes alcohol at a rate of 0.015% BAC per hour. Two beers may keep you above 0.00% for 2–4 hours, depending on your body weight, sex, metabolism, and the alcohol content of the beer. Factors like food intake and hydration can influence this, but you should never rely solely on time estimates to determine sobriety.

Drinking and driving laws differ by country and often have stricter limits for certain groups of drivers. Our Country-by-Country BAC Law Table includes over 50 countries with their official BAC limits and special notes. Penalties can include fines, license suspension, vehicle impoundment, and even jail time.

A BAC of 0.05% (also written as 0.5‰ or 0.5 per mille) means there are 0.05 grams of pure alcohol per 100 milliliters of blood. In practical terms, this can be reached with about 2–3 standard drinks for an average adult, but this varies greatly by body weight, gender, and drinking speed.

A BAC of 0.02% (0.2‰) is typically reached after about 1 drink for many adults. However, smaller individuals or those with slower metabolism may reach this level with less. In many countries, 0.02% is the legal limit for novice or professional drivers.

In public health terms, heavy drinking often means consuming more than:

• For men: 15 drinks per week.
• For women: 8 drinks per week.

0.5‰ BAC often equals about 2–3 beers for an average adult male, or 1.5–2 beers for an average adult female. This is a rough estimate — BAC depends on body weight, metabolism, and beer alcohol content.

Promille (per mille) is a unit meaning "parts per thousand" (‰). In BAC measurement, 0.5‰ equals 0.05%, or 0.05g of pure alcohol per 100mL of blood. Many European countries use promille instead of percentage when stating legal alcohol limits.

In Germany:

• 0.5–1.09‰: €500 fine, 1-month driving ban (first offense).
• Over 1.1‰: Criminal offense, possible prison sentence, license suspension.

On average, the body eliminates alcohol at about 0.015% BAC per hour. This equals roughly one standard drink per hour, though this rate varies by individual.

For many people, 3 beers can be detected on a breathalyzer for 4–6 hours. This depends on your size, metabolism, and whether you’ve eaten food.

A single sip of alcohol may register briefly on a breathalyzer for a few minutes, but is unlikely to result in a measurable BAC unless swallowed in larger quantity. However, mouth alcohol can cause temporary false positives.

Three drinks in one sitting may be considered binge drinking for smaller individuals or those with lower alcohol tolerance. Public health agencies define binge drinking as:

• Men: 5+ drinks in 2 hours
• Women: 4+ drinks in 2 hours

Drinking water does not directly lower BAC, but it can reduce dehydration and hangover effects. Only time allows your body to metabolize alcohol. For each standard drink, allow at least 1 hour for your body to process it fully.