Tagespegel – Blood Alcohol Calculator

For pure blood alcohol level: your liver doesn't care about the order in which the alcohol arrived. What matters is the total amount of pure alcohol, your body weight and time – exactly the quantities this calculator works with. Whether beer first then wine or the other way round: with the same amount of alcohol you end up at the same BAC.

The saying persists anyway, and it has a psychological kernel. Someone who starts with light beer and later switches to high-proof wine or spirits often unnoticeably drinks more alcohol faster – the level climbs more steeply than it feels. So switching “upwards” encourages overdoing it, not the order itself.

A controlled study by the University of Witten/Herdecke and the University of Cambridge (2019) found no evidence that the order affects the hangover – neither the type nor the order of drinks changed hangover severity significantly. In short: the hangover comes from the amount, not the choreography. “Beer before wine” is more a memory aid for moderation than a biological truth.

The warming feeling after a digestif is real, but the mechanism behind it is different than thought. Alcohol tends to slow gastric emptying rather than speed it up. So heavy, rich food actually stays in the stomach longer – the shot merely masks the feeling of fullness because alcohol dulls perception and relaxes the muscles.

What many experience as a “digestive aid” is mainly the bitter herbal content of many digestifs: bitter compounds can stimulate the flow of saliva and gastric juices. But you don't need alcohol for that – a bitter tea or an alcohol-free herbal extract does the same without raising your level.

For your alcohol level the shot counts as normal: 2 cl at 40 % is around 6 grams of pure alcohol. As a cosy end to a meal there's little to object to – you just “digest” despite it rather than because of it.

Unfortunately no. The body eliminates alcohol at a largely fixed rate – around 0.1 to 0.15 ‰ per hour, regardless of what else you do. This breakdown happens almost entirely via the liver and cannot be sped up noticeably by coffee, cold showers, fresh air, exercise or vomiting.

Coffee and other stimulants do exactly that: they make you alert. That's actually treacherous, because caffeine masks tiredness without removing the impairment of reaction, judgement and coordination. You feel fitter than you are – dangerous above all behind the wheel.

The only thing that really helps is time. That's exactly what the “sober from” estimate in this calculator shows you: a rough forecast of when your level is calculated to be back at 0.0 ‰. Until then no trick helps – only waiting.

There's something to the saying on average, but the explanation is more biological than cultural. Alcohol is distributed in body water, and muscle tissue holds considerably more water than fatty tissue. Because the female body has a somewhat higher fat percentage on statistical average, the same amount of alcohol is distributed across less body water – so the BAC comes out higher.

That's exactly what the so-called Widmark distribution factor reflects: this calculator uses around 0.68 for men and 0.55 for women. With the same weight and the same amount consumed, women therefore end up with a higher calculated level. On top of that, women have on average slightly less of the alcohol-degrading enzyme alcohol dehydrogenase in the stomach.

The important word is “average”: a muscular, light man can have a worse value than a sturdy woman. The factor is an approximation for the population average, not an individual measurement – your personal daily condition can differ considerably.

There's a true kernel here. Food – especially fatty and protein-rich food – keeps alcohol in the stomach longer before it reaches the small intestine, where most of it passes into the blood. Absorption is thus spread over a longer period, the peak value is lower and the rise gentler.

But: food only changes the pace of absorption, not the total amount. The alcohol you drank ends up completely in the blood sooner or later. On an empty stomach the level shoots up faster and higher; on a full stomach it's flatter and delayed – the area under the curve stays similar, and in the end the same amount has to be broken down.

For road traffic that means: a good meal doesn't protect you from excessive values, it just shifts them in time. This calculator assumes, in simplified terms, a fixed absorption time and can therefore only roughly reflect food effects.

Falling asleep yes, sleeping well no. Alcohol has a sedative effect and often shortens the time it takes to fall asleep – hence the feeling that it helps. But as soon as the body starts breaking it down, the effect flips: the second half of the night becomes more restless, with more frequent waking and shallower sleep.

REM sleep – the dream phase important for recovery and memory – suffers in particular. Alcohol suppresses it at first, and later the body “catches up” in fragments – the result is vivid dreams, sweating and the familiar waking at four in the morning. The relaxing effect on the throat muscles also increases snoring and breathing pauses.

The bottom line: after a nightcap you fall asleep faster but sleep worse through the night – and wake up less rested. As a sleep aid, alcohol is therefore a bad deal that additionally fuels the next morning's hangover.

The price is the wrong trail. The main cause of a hangover is simply the amount of alcohol plus its effect as a cell toxin and diuretic – and that's chemically identical in expensive and cheap drinks. Whoever drinks a lot gets a hangover, no matter what's on the label.

There is a small true kernel with the so-called congeners (fusel alcohols and flavour compounds). Dark spirits like whisky, cognac or red wine contain more of them than clear ones like vodka or gin, and these substances are suspected of intensifying the hangover. But the congener content has little to do with price – an expensive whisky can contain more of them than a cheap vodka.

What often softens the hangover with premium drinks is drinking behaviour: you sip good wine more slowly and in smaller amounts than cheap sparkling wine at a party. So it's not the price that saves you, but the pace and quantity.

Habituation mainly changes how the alcohol feels – not how much is in the blood. Regular drinkers develop a tolerance: the brain reacts less sensitively, so you seem and feel less drunk at the same level. But the BAC itself is exactly the same as for an inexperienced drinker.

That's the real danger of this “tolerance”: you underestimate your own state. At a traffic check only the measured value counts, not the subjective feeling of sobriety. Someone at 1.3 ‰ who feels fine is nonetheless in the criminally relevant range.

In the long term a high tolerance is also a warning sign, not a compliment: it shows the body has adapted to regular consumption and often goes hand in hand with rising amounts. This calculator knows nothing of habituation – it shows you the sober numerical value, regardless of how “safe” you feel.

The notorious alcohol breath hardly arises in the mouth, but in the lungs. As soon as alcohol circulates in the blood, some of it passes into the breath via the alveoli – so you can be smelled as long as measurable alcohol is in the blood. Alcohol breath is therefore not superficial bad breath but a direct reflection of your level, which is why the smell remains even after brushing your teeth.

As a rough rule of thumb: as long as your level is above zero, you can potentially be smelled – and because the body eliminates only slowly, that can last many hours, after a boozy night well into the next morning. The typical “morning after” smell is exactly this residual alcohol still being broken down. Alcohol also causes a drier mouth and encourages odour-forming bacteria, which amplifies the effect.

Against the actual alcohol breath, neither chewing gum nor coffee nor mouthwash helps – at best they cover the smell briefly while alcohol keeps coming from the lungs. The only thing that really makes the smell disappear is the same factor as with the level: time. When the smell is gone, that roughly means the alcohol is largely broken down too – but you can't read a blood value from it.