Alcohol Metabolism Chart: How Long Each Drink Takes to Burn Off

Ask a bartender how long a drink takes to wear off and you'll hear "about an hour," which is the answer that sends a lot of people home too early. The real number depends on how many standard drinks you had, what you weigh, and how fast your liver happens to be running tonight. We can't see your liver. We can do the first two exactly the way our BAC calculator does, at 2 a.m. or any other hour.

Two related questions live elsewhere. Drug-test detection windows for urine, breath and hair are covered in how long alcohol stays in your system. Peak BAC by weight is in the blood alcohol chart by weight. This page is about the clock.

How These Numbers Were Made

Nothing in these tables was typed in by hand. Every cell is computed at build time by the same code behind our BAC Calculator and Sober Calculator, so the chart and the tools cannot disagree with each other.

• One standard drink is 14 grams of pure alcohol, the NIAAA definition.
• Widmark body-water factors: 0.68 for men, 0.55 for women.
• Elimination rate: 0.015% BAC per hour, a straight line down.
• Drinks finished within a short window on an empty stomach, and the clock starts at the first drink.

The methodology page lists every constant and where it comes from.

Hours to 0.00% BAC — Men

Hours to 0.00% BAC — Women

Cell color shows the estimated peak BAC behind each time: green under 0.05%, amber from 0.05%, red from 0.08% (the legal limit in most states), deep red from 0.15%, and the darkest shade from 0.30%, where an overdose is a real possibility.

Times are rounded to the nearest 5 minutes.

The 180-pound male column makes the cost of each round clear: 3 hours 20 minutes for two drinks, 6 hours 45 minutes for four, just over 10 hours for six.

That's roughly 100 extra minutes per drink, so every extra round pushes your morning back by well over an hour and a half. A woman at the same weight pays about a quarter more per drink, since the same alcohol lands in less body water.

Here's the part that trips people up on a Saturday night. In this math, nursing six beers from 8 to 11 instead of finishing them by 9 doesn't move the finish line, as long as your BAC never hits zero in between.

The liver starts its fixed hourly work with the first sip and never speeds up to clear a backlog. Slower drinking keeps the peak lower, which matters for impairment. It doesn't hand the hours back.

BAC by the Hour: How Fast the Number Falls

This second chart skips drink counts and starts from a BAC you already have, say from a breath test or our calculator. Each row is one more hour of the liver working at 0.015% per hour. Bold values are still at or above 0.08%.

Look at the column starting at 0.15%. Someone at that level needs about 4 hours 40 minutes to drop under 0.08% and 10 hours to reach zero.

Stop drinking at 1 a.m. at that level and the table keeps you over the legal limit until about 5:40 a.m., with measurable alcohol still on board at 10, right when plenty of people drive to brunch.

What Your Liver Is Actually Doing

If you've ever tried to sweat a night out at the gym, the numbers are against you. Cederbaum's 2012 review in Clinics in Liver Disease reports that about 90% of alcohol is removed by oxidation, mostly in the liver, and under 10% leaves unchanged through breath, sweat and urine. With the liver doing nine-tenths of the work, nothing you do on the outside changes how much enzyme it has on hand tonight.

The chemistry runs in two steps:

• Step one. Alcohol dehydrogenase (ADH) in liver cells converts ethanol into acetaldehyde.
• Step two. Aldehyde dehydrogenase, mainly ALDH2 inside the mitochondria, converts acetaldehyde into acetate.

NIAAA scientist Samir Zakhari, writing in Alcohol Research & Health (2006), calls acetaldehyde a highly reactive, toxic byproduct that may contribute to tissue damage.

That middle step gets far less attention than it deserves. Breathalyzers and every chart on this page measure ethanol only, so they can't tell you how much acetaldehyde your body is still clearing.

Why the Line Is Straight: Zero-Order Kinetics

A. W. Jones' 2010 review of forensic elimination studies in Forensic Science International explains the straight line. Liver ADH is saturated after the first few drinks, so above roughly 0.02% BAC it already works flat out.

The decline then follows zero-order kinetics: a fixed amount per hour, not a fixed percentage. Doubling your BAC never doubles the clearing speed. It only doubles the wait.

Below about 0.02% the enzyme is no longer saturated and the decline bends into a slower tail. The last few thousandths of a percent can take a little longer than the straight line suggests.

How Much the Rate Varies

Jones' review gives the most useful numbers here. Moderate drinkers average about 0.015% per hour, the rate our tables use. People measured on an empty stomach clear 0.010% to 0.015% per hour, people who have eaten 0.015% to 0.020%, and alcoholics in detox, whose CYP2E1 enzymes have been ramped up by heavy drinking, can reach 0.025% to 0.035%. That full spread is more than threefold, which is wide enough to move any single cell in these tables by hours.

That empty-stomach range is the uncomfortable part. Our tables use an empty stomach for the peak but 0.015% per hour for the decline, the top of the fasting range Jones reports.

If you drank without eating, your real wait could be longer than the cell says, not shorter. Treat every number here as a floor, not a promise.

The main reasons one person clears faster or slower than another:

• Enzyme genetics. Cederbaum notes that ADH variants (ADH1B, ADH1C) differ between populations, and that human elimination rates vary three- to fourfold overall.
• ALDH2. Inactive ALDH2 turns up in 15 to 40% of people in East Asia, and their blood acetaldehyde runs 5 to 20 times higher after drinking. This hits the second step, not the ethanol line on this chart.
• Heavy drinking. Chronic heavy use raises the metabolic rate, partly by inducing CYP2E1. Faster clearance in a heavy drinker is adaptation, not a sign of being fine.
• Sex. Jones found BAC falls slightly faster in women, which seems to be related to liver size relative to lean body mass. It is small next to the body-water gap, so women's tables still run longer.
• Food. A meal before or with drinks lowers the peak, and fed people clear a bit faster. Food eaten afterwards can't pull alcohol back out of your blood.
• Everything else. Zakhari lists diet, age, smoking and even time of day among the factors that shift the rate.

The "One Drink Per Hour" Rule, Checked Against the Math

Cederbaum's 2012 review gives the liver's average capacity as about 7 grams of alcohol an hour for a 70-kilogram adult, and then calls that roughly one drink an hour. By US math it's half of one, since a standard drink here is 14 grams, which turns a comfortable rule into a wait twice as long. Our tables show the same thing: about 2 hours for one drink at 150 pounds if you're a man, 2 hours 30 minutes if you're a woman.

So the rule runs optimistic for most people, and it falls apart completely once the drinks stop being standard:

• A 12-ounce craft beer at 10% ABV is two standard drinks, by NIAAA's own math.
• Just 8 to 10 ounces of malt liquor or a flavored malt beverage at about 7% already counts as one.
• A double shot is two drinks before the mixer even goes in, and a generous wine pour is more than one.

Convert what is actually in the glass with the standard drinks calculator before reading the tables, or the hours will be wrong from the first row.

What Doesn't Speed It Up

NIAAA's overdose guidance is direct: cold showers, hot coffee and walking do not reverse the effects of alcohol overdose. Coffee can make you feel sharper while your BAC stays exactly where the table says it is.

Sleep isn't a shortcut either. Sleep doesn't speed the liver up, so eight hours of sleep clears roughly eight hours' worth and no more.

Our guide on how to sober up fast walks through each of these myths and what actually helps.

When the Numbers Become an Emergency

NIAAA warns that BAC can keep rising after someone stops drinking or even passes out, because alcohol still in the stomach and intestine keeps absorbing.

So the darkest cells in these tables describe a medical situation, not a waiting game. NIAAA also calls it dangerous to assume an unconscious person will be fine sleeping it off. Somebody needs to stay with them.

NIAAA's critical warning signs include:

• Mental confusion or stupor, or being impossible to wake.
• Vomiting or seizures.
• Slow breathing (fewer than 8 breaths a minute) or 10 seconds or more between breaths.
• Slow heart rate, clammy skin, or very low body temperature with bluish or pale skin.

If you see these signs, call 911 right away. Our guide to alcohol poisoning symptoms covers what to do while help is on the way.

Using This Chart Without Fooling Yourself

This chart is for planning the next morning, not for deciding whether you can drive tonight. Dropping under 0.08% means you are below the legal limit in most states, not that you are unimpaired.

Our methodology puts realistic uncertainty at about 25 to 35%, enough to push a borderline cell onto the wrong side of the line. If a table says you are close, assume you are not there yet and book the ride.

For an estimate built from your own drinks and timing, use the BAC Calculator. If you already know your BAC, the sober calculator turns it into a clock time. For the interactive weight grid, see the BAC chart.

If drinking has started to feel like a problem, SAMHSA's National Helpline is free, confidential and open 24/7 at 1-800-662-4357.

Sources

• Jones AW. Evidence-based survey of the elimination rates of ethanol from blood with applications in forensic casework. Forensic Science International. 2010;200(1-3):1-20. DOI: 10.1016/j.forsciint.2010.02.021.
• Cederbaum AI. Alcohol Metabolism. Clinics in Liver Disease. 2012;16(4):667-685. DOI: 10.1016/j.cld.2012.08.002. Full text: PMC3484320.
• Zakhari S. Overview: How Is Alcohol Metabolized by the Body? Alcohol Research & Health (NIAAA). 2006;29(4):245-254. PMC6527027.
• NIAAA. What Is a Standard Drink? niaaa.nih.gov.
• NIAAA. Understanding the Dangers of Alcohol Overdose. niaaa.nih.gov.
• SAMHSA National Helpline: 1-800-662-4357. samhsa.gov.