Your body eliminates alcohol at a fairly steady rate of about 0.015% blood alcohol concentration (BAC) per hour, which works out to roughly one standard drink every 60 to 90 minutes. 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.
How Fast Your Body Clears Alcohol
Your liver does the heavy lifting. An enzyme in your liver and stomach cells breaks ethanol down into a toxic intermediate compound, which a second enzyme then converts into something harmless your body can use for energy. The catch is that the first enzyme maxes out quickly, even at low alcohol levels. Once it’s working at full capacity, it can’t speed up no matter how much alcohol is waiting in line. That’s why your BAC drops at a nearly fixed rate rather than clearing faster when you’ve had more to drink.
For most moderate drinkers, that fixed rate is about 15 mg/dL per hour (equivalent to a 0.015% BAC drop). The full physiological range runs from 10 to 35 mg/dL per hour, but most people fall in the middle. Drinking on an empty stomach tends to push you toward the slower end, around 10 to 15 mg/dL per hour. People who drink heavily and regularly can metabolize alcohol faster, sometimes 25 to 35 mg/dL per hour, because chronic exposure ramps up a backup enzyme system in the liver. That faster clearance isn’t a health advantage; it comes with increased production of toxic byproducts that damage liver cells.
Rough Timelines by Number of Drinks
A standard drink in the United States contains 0.6 ounces (14 grams) of pure alcohol. That’s 12 ounces of regular beer at 5%, 5 ounces of wine at 12%, or a 1.5-ounce shot of 80-proof liquor. Many cocktails and craft beers contain significantly more than one standard drink per serving, so count carefully.
Using the average clearance rate of 0.015% BAC per hour, here’s a general guide for how long it takes to reach 0.00% after your last sip. These assume you’re an average-sized person who stopped drinking and waited:
- 1 to 2 standard drinks: roughly 2 to 3 hours
- 3 to 4 standard drinks: roughly 4 to 6 hours
- 5 to 6 standard drinks: roughly 7 to 10 hours
- 8 or more standard drinks: 12 hours or longer
These are estimates. A smaller person drinking the same amount will reach a higher peak BAC and take longer to clear it. The numbers also assume your liver is healthy and functioning normally.
Why It Takes Longer for Some People
Body composition is the biggest variable. Alcohol dissolves in water, not fat, so your BAC depends on how much water your body contains. People with more muscle mass and larger frames have more body water to dilute the alcohol, producing a lower peak BAC from the same number of drinks. People with higher body fat percentages, smaller frames, or less muscle mass reach higher BAC levels and need more time to clear it.
Women generally absorb more alcohol and take longer to process it than men, even at the same body weight. This is partly because women tend to have a higher ratio of body fat to water and partly because of differences in enzyme activity. The CDC notes that women typically reach higher blood alcohol levels after drinking the same amount as men.
Food makes a meaningful difference in how quickly alcohol hits your bloodstream. When you drink on an empty stomach, alcohol passes rapidly into the small intestine, where it’s absorbed fast. Eating a meal before or while drinking slows gastric emptying, keeping alcohol in the stomach longer. Research published in the American Journal of Physiology found that food increased first-pass metabolism of alcohol from about 4% to 30% of the dose, meaning your body breaks down more alcohol before it ever reaches general circulation. The practical result: eating doesn’t speed up elimination, but it lowers your peak BAC, which means less total time before you’re back to zero.
How Long Alcohol Shows Up on Tests
Your body may reach a BAC of 0.00% hours before certain tests stop detecting that you drank. Different testing methods look for different things, and their detection windows vary widely.
- Breath test (breathalyzer): Detects alcohol for 4 to 6 hours after drinking, sometimes up to 24 hours.
- Blood test (standard): Measures BAC and detects alcohol within the last 12 hours.
- Urine test (standard ethanol): Detects alcohol for about 12 hours.
- Urine test (EtG/EtS): Detects a metabolic byproduct of alcohol for 24 to 48 hours after a few drinks, and up to 72 hours or more after heavier drinking.
- Blood test (PEth): Detects a marker of alcohol use for 1 to 3 weeks, sometimes longer after prolonged heavy drinking.
- Saliva test: Detects alcohol for up to 24 hours.
The EtG urine test deserves special attention because it’s commonly used in court-ordered monitoring, workplace testing, and treatment programs. Unlike a standard urine test that looks for alcohol itself, the EtG test detects a breakdown product your body produces when it processes ethanol. This byproduct lingers in urine long after the alcohol is gone from your blood. After moderate drinking, expect it to show up for about two days. After a heavy session, 72 hours or longer is realistic.
What Doesn’t Speed Things Up
Coffee, cold showers, exercise, and drinking water will not help your liver process alcohol faster. Your liver’s primary alcohol-metabolizing enzyme works at a fixed maximum speed regardless of what else you do. Hydration and food can affect how you feel and may reduce hangover severity, but they don’t change the rate at which alcohol leaves your blood. The only thing that clears alcohol is time.
BAC and Legal Limits
In 49 U.S. states, the legal driving limit is 0.08% BAC. Utah sets it lower at 0.05%. For drivers under 21, every state enforces a limit of 0.02% or lower. Some states also impose reduced limits of 0.02% to 0.04% for people with prior DWI convictions. The National Transportation Safety Board has recommended lowering the national limit to 0.05% for all drivers.
Keep in mind that impairment begins well before 0.08%. Reaction time, judgment, and coordination all degrade at BAC levels as low as 0.02% to 0.04%. If you’ve been drinking and feel fine, that feeling itself can be a symptom of impairment, since alcohol affects your ability to accurately judge your own state. The safest approach is to calculate your likely BAC based on what you drank, assume the slower end of the clearance range (0.015% per hour), and add a buffer before driving.