Your body clears alcohol at a roughly fixed rate of about 0.015% blood alcohol concentration (BAC) per hour, which works out to a little less than one standard drink every 60 to 90 minutes for most people. So if you stop drinking at midnight with a BAC of 0.08% (the legal limit in most U.S. states), you won’t hit 0.00% until around 5:30 a.m. at the earliest. The exact timeline depends on how much you drank, your body size, your sex, and whether you ate beforehand.
What Counts as One Drink
Before you can estimate your timeline, you need to know what “one drink” actually means. In the United States, one standard drink contains about 14 grams (0.6 fluid ounces) of pure alcohol. That’s the amount in a 12-ounce can of regular beer at 5% alcohol, a 5-ounce glass of wine at 12%, or a 1.5-ounce shot of spirits at 40% (80 proof).
Most people undercount. A strong IPA at 8% alcohol in a pint glass is closer to two standard drinks. A generous pour of wine can easily be 7 or 8 ounces, pushing it to 1.5 drinks. A cocktail with two shots is two drinks, not one. Getting an honest count is the single biggest factor in estimating your clearance time.
A Simple Way to Estimate Your Timeline
Because the liver processes alcohol at a nearly constant rate regardless of how much is in your system, the math is straightforward. Each standard drink adds roughly one to one and a half hours to the clock. Two drinks means about two to three hours. Four drinks means roughly four to six hours. Six drinks could take eight hours or more to fully clear.
These are rough estimates for an average-sized adult. The formula toxicologists use (called the Widmark equation) factors in body weight, biological sex, the number of drinks, and the time you spent drinking. You don’t need to run the equation yourself, but knowing the variables helps you understand why your experience might differ from a friend’s.
Why Clearance Times Vary From Person to Person
Several biological factors shift the timeline in meaningful ways.
Body size and composition. Alcohol distributes through body water. A larger person with more water volume will dilute the same number of drinks to a lower BAC, meaning less total time to reach zero. Men generally carry more body water and less body fat than women of similar weight, which gives them a larger distribution volume and a lower peak BAC per drink.
Biological sex. Women typically reach a higher BAC than men after the same number of drinks, even at the same body weight, partly because of that difference in body composition. Interestingly, research in Gastroenterology has shown that women actually clear alcohol faster per unit of lean body mass than men do. But because women start at a higher peak, the net result is often a longer total wait to hit zero.
Food in your stomach. Eating before or while you drink slows the rate at which alcohol reaches your small intestine, where most absorption happens. This doesn’t just lower your peak BAC. According to data from Johns Hopkins University, having food in your system increases the rate of alcohol elimination from your blood by 25 to 45%. That’s a significant difference. Drinking on an empty stomach means faster absorption, a higher peak, and a longer wait.
Nothing Speeds Up Your Liver
Coffee, cold showers, energy drinks, exercise, greasy food after drinking: none of these change how fast your liver breaks down alcohol. Caffeine can make you feel more alert, which is actually dangerous because it masks how impaired you still are. The enzymes responsible for processing alcohol work at their own pace, and no substance or activity accelerates them. Time is the only thing that sobers you up.
How Long Alcohol Shows Up on Different Tests
Even after you feel completely sober, alcohol or its byproducts can still be detected depending on the type of test. This matters if you’re facing a workplace screening, a probation check, or a medical procedure.
- Breath test: A breathalyzer can detect alcohol for up to 24 hours after your last drink, though for moderate drinking the window is usually much shorter.
- Blood test: Alcohol is detectable in blood for up to 12 hours.
- Urine test: Standard urine tests catch alcohol for a day or so, but specialized urine tests that look for a metabolite called EtG can detect evidence of drinking for up to 5 days.
- Hair follicle test: Hair testing can reveal alcohol use up to 90 days back, though it’s more commonly used to identify patterns of heavy drinking than a single occasion.
The blood and breath windows track closely with how long your body is actively processing the alcohol. The urine and hair windows are longer because they detect metabolic byproducts that linger after the alcohol itself is gone.
Practical Examples
Here’s what the math looks like for a few common scenarios, assuming an average-sized adult who ate a normal meal:
Two glasses of wine at dinner, finishing around 8 p.m.: You’re likely clear by 10 to 11 p.m. A breathalyzer would probably read zero well before midnight.
Four beers over a few hours at a weekend barbecue, stopping at 6 p.m.: Expect your BAC to reach zero somewhere around 10 p.m. to midnight, depending on your size and sex.
Six or more drinks at a party, finishing at 1 a.m.: You could still have a measurable BAC when you wake up at 7 a.m. This is how people end up driving over the legal limit the morning after, genuinely believing they’re fine.
That last scenario is more common than most people realize. If your BAC peaked at 0.12% and your liver clears 0.015% per hour, it takes eight hours just to get back to zero. Factor in the time between your last drink and your peak BAC (usually 30 to 60 minutes after you stop drinking), and the math gets even less forgiving.