Your liver processes alcohol at a steady rate of about one standard drink per hour. That means if you have three drinks, it takes roughly three hours for your body to fully eliminate the alcohol from your blood. But “how long alcohol lasts” depends on what you’re really asking: how long until you’re sober, how long until you can drive, how long until a test can’t detect it, or how long until you actually feel normal again. Each of those has a different answer.
How Your Body Breaks Down Alcohol
Two enzymes in the liver do nearly all the work. The first breaks the alcohol molecule into a toxic intermediate compound, and the second breaks that compound into something harmless your body can dispose of. This process runs at a remarkably fixed speed. Unlike most substances, where doubling the dose just means a higher peak that fades at the same rate, alcohol creates a bottleneck. Your liver can only handle so much at once, so extra drinks simply wait in line.
That one-drink-per-hour rate is an average. Several factors shift it in either direction: your body weight, biological sex, age, genetics, overall nutrition, and whether you ate before drinking. People with certain genetic variations in those liver enzymes process alcohol noticeably faster or slower. Women generally reach higher blood alcohol levels than men after the same number of drinks, partly because of differences in body water content and enzyme activity. None of these factors change the fundamental reality that time is the only thing that clears alcohol from your system.
Nothing Speeds It Up
Coffee, cold showers, exercise, fresh air: none of these help your liver work faster. Caffeine can make you feel more alert, but your blood alcohol concentration stays the same. Exercise does push tiny amounts of alcohol out through sweat and breathing, but the effect is negligible. The only reliable path to sobriety is waiting.
How Long Until You’re Sober
A rough guide based on the one-drink-per-hour rule:
- 1 drink: about 1 to 2 hours
- 3 drinks: about 3 to 4 hours
- 5 drinks: about 5 to 7 hours
- 8+ drinks: 8 hours or more, potentially into the next morning
Keep in mind that your first drink doesn’t start its one-hour clock until it’s absorbed, which takes 15 to 45 minutes depending on whether your stomach is empty. If you’re drinking over several hours, the math stacks: your liver is processing earlier drinks while new ones keep arriving.
How Long Effects Actually Last
Here’s what surprises most people. Even after alcohol has technically left your bloodstream, you can still feel impaired. If your blood alcohol concentration reached 0.06 or higher (roughly two to three drinks for many adults), the aftereffects on your brain, coordination, and judgment can linger for up to 72 hours. That means drinks on a Saturday night could still be affecting your focus and reaction time on Tuesday, with real consequences for work or driving on Wednesday.
This goes well beyond a hangover headache. Disrupted sleep, slower processing speed, and subtle coordination problems persist even when you feel “fine.” Your blood alcohol might read zero, but your brain hasn’t fully recalibrated.
Detection Windows by Test Type
If you’re wondering how long alcohol shows up on a test, the answer varies dramatically depending on the type:
- Blood and breath tests: These detect alcohol for roughly the same window your body takes to metabolize it. For moderate drinking, that’s typically 12 to 24 hours at most.
- Standard urine tests: Alcohol itself clears from urine within about 12 hours. However, a more sensitive urine test looks for a metabolic byproduct called EtG, which sticks around much longer: up to 48 hours after a few drinks, and 72 hours or more after heavier drinking.
- Hair tests: A hair strand test can detect alcohol use from 1 to 6 months in the past. These tests look for EtG markers deposited in the hair as it grows and are typically used to assess drinking patterns over time rather than a single episode.
How Long Alcohol Stays in Breast Milk
Alcohol levels in breast milk mirror blood alcohol levels almost exactly. The concentration peaks 30 to 60 minutes after a drink. From there, it clears at roughly the same rate as blood alcohol, following a predictable pattern based on how much you drank:
- 1 drink: detectable in breast milk for about 2 to 3 hours
- 2 drinks: about 4 to 5 hours
- 3 drinks: about 6 to 8 hours
The same individual factors apply here: body weight, how quickly you drank, and whether you ate alongside the alcohol all influence the timeline. As your blood alcohol falls, so does the alcohol in your milk. Pumping and dumping does not speed this process. The milk your body produces after alcohol has cleared from your blood will be alcohol-free without any need to discard it.
Driving and Legal Limits
Every U.S. state sets the legal blood alcohol limit at 0.08, with one exception: Utah uses a lower limit of 0.05. For drivers under 21, the limit drops to 0.02 or lower nationwide. Some states, including Colorado and New York, also have separate charges for impairment at levels below 0.08.
For a 160-pound person, two standard drinks in an hour might put blood alcohol around 0.04 to 0.05. Three drinks could push past 0.08. But because individual metabolism varies so much, counting drinks and guessing your number is unreliable. The only certain way to be at zero is to wait long enough. A night of four or five drinks ending at midnight means your blood alcohol may not reach zero until 5 or 6 a.m., and the residual cognitive effects can extend well beyond that.
What Counts as One Drink
All of these timelines assume a “standard drink,” which contains about 14 grams of pure alcohol. In practice, that’s 12 ounces of regular beer (around 5% alcohol), 5 ounces of wine (around 12%), or 1.5 ounces of distilled spirits (around 40%). Craft beers, heavy pours of wine, and cocktails with multiple shots often contain significantly more alcohol than one standard drink, which throws off any mental math you’re doing about how long until you’re clear.