Alcohol is fully eliminated from your bloodstream at a rate of about 0.015 to 0.020 blood alcohol concentration (BAC) per hour. For someone at the legal driving limit of 0.08 BAC, that means roughly 4 to 5 hours to reach zero. But “in your system” depends on what you mean: breath and blood tests detect alcohol for hours, urine tests for days, and hair tests for months.
How Fast Your Body Clears Alcohol
Your liver does the heavy lifting, processing alcohol at a steady, fixed rate that you can’t speed up with coffee, water, or food. At typical drinking levels, your body clears about 0.015 to 0.020 BAC per hour. This rate is largely constant regardless of how much you’ve drunk, a pattern pharmacologists call zero-order elimination. Your liver’s alcohol-processing enzymes are essentially maxed out after even one or two drinks, so additional alcohol just waits in line.
Once your BAC drops below about 0.02, the rate slows down further because your liver is no longer working at full capacity. At very low concentrations (below 0.01), clearance can drop to roughly half the normal speed. In practical terms, this means the last traces of alcohol linger a bit longer than you’d expect from simple math.
Detection Windows by Test Type
The answer to “how long is alcohol in your system” changes dramatically depending on the test being used:
- Breath (breathalyzer): Detects alcohol for roughly 12 to 24 hours after your last drink, depending on how much you consumed.
- Blood: Similar to breath, up to about 12 hours for moderate drinking.
- Standard urine: Alcohol itself appears in urine for about 12 to 24 hours.
- EtG urine test: This test looks for a byproduct your body creates when it breaks down alcohol. It can detect drinking for 24 to 72 hours after your last drink, and some tests claim sensitivity up to 80 hours, though the chance of a false negative rises sharply after 24 hours.
- Hair follicle: Alcohol markers show up in hair for 1 to 6 months, making this the longest detection window available.
EtG tests are common in court-ordered monitoring, workplace programs, and probation. The sensitivity depends on the threshold being used. Clinical settings typically use a cutoff of 100 nanograms per milliliter, which catches lighter drinking. Criminal courts generally use a higher threshold of 500 nanograms per milliliter, which reduces false positives but only flags heavier or more recent consumption.
Factors That Change Your Clearance Rate
While the average elimination rate is consistent, several biological factors determine where you fall within the range and how high your BAC climbs in the first place.
Body size and composition. People with more body water dilute alcohol more effectively, producing a lower peak BAC from the same number of drinks. Muscle tissue holds more water than fat, so two people at the same weight can have very different BAC levels based on their body composition.
Biological sex. Women generally absorb more alcohol and take longer to process it than men. This is partly because women tend to have less body water and more body fat relative to their size, and partly because of differences in hormone levels that affect how alcohol is metabolized. A woman and a man drinking the same amount will typically see different BAC readings, with the woman’s being higher.
Liver health. Your liver handles over 90% of alcohol metabolism. Any condition that impairs liver function, including fatty liver disease, hepatitis, or cirrhosis, slows clearance. Chronic heavy drinking gradually damages the liver’s ability to process alcohol efficiently, creating a compounding problem.
Food in your stomach. Eating before or while drinking slows the absorption of alcohol into your bloodstream. It doesn’t change how fast your liver works, but it lowers your peak BAC, which means less total time to reach zero.
Estimating Your Timeline
A standard drink in the United States contains about 14 grams of pure alcohol. That’s one 12-ounce beer at 5%, one 5-ounce glass of wine at 12%, or one 1.5-ounce shot of 80-proof liquor. Each standard drink raises your BAC by roughly 0.02 to 0.03, though this varies with body size and sex.
Using the average clearance rate of 0.015 per hour, you can do rough math. Three standard drinks might bring a 180-pound man to a BAC of about 0.06. From there, it would take approximately 4 hours to reach zero. The same three drinks could bring a 130-pound woman to 0.09 or higher, requiring 6 or more hours to fully clear.
These are estimates. There is no reliable way to know your exact BAC without a breathalyzer or blood test, and “feeling sober” is not the same as being at zero. Impairment in reaction time and judgment can persist even as your BAC drops below the legal limit.
Alcohol Clearance From Breast Milk
Alcohol enters breast milk at roughly the same concentration as your blood, and it clears from milk at the same rate. You don’t need to “pump and dump” because alcohol doesn’t get trapped in milk. Once it’s out of your blood, it’s out of your milk.
The timeline depends on body weight and the number of drinks. For a 130-pound woman, one drink clears from breast milk in about 2 hours and 24 minutes. Two drinks take closer to 4 hours and 49 minutes. Three drinks take roughly 7 hours and 13 minutes. A 160-pound woman clears one drink in about 2 hours and 10 minutes, two drinks in 4 hours and 20 minutes, and three drinks in 6 hours and 30 minutes. Each additional drink adds roughly 2 to 2.5 hours to the total wait time.
Why You Can’t Speed It Up
No supplement, food, or home remedy accelerates alcohol metabolism in any meaningful way. Your liver processes alcohol at its own fixed rate, and that rate is determined by your genetics, liver health, and enzyme levels. Cold showers, exercise, and black coffee might make you feel more alert, but they don’t lower your BAC or help you pass a test any sooner. The only thing that clears alcohol from your system is time.