How long does alcohol stay in your system?
Two different questions hide in that sentence. How long are you impaired: hours, set by your liver's fixed pace. How long can a test find evidence: up to days for urine, months for hair. This page answers both, with the sources visible.
What did you drink?
- Beer330 mL can/bottle, 5%0
- Pint of beer500 mL, 5%0
- Glass of wine150 mL, 12.5%0
- Shot40 mL, 40%0
- Cocktailabout two shots of spirits0
- Hard seltzer330 mL, 4.5%0
Total: about 0.0 US standard drinks (0 g of alcohol). Odd pour? Convert it here.
We assume it was within the last 24 hours.
Credits what your liver cleared while you were still drinking. Skipping it keeps the most cautious estimate.
Sex
Sets the Widmark body-water ratio. Skipping is fine; it just widens the range.
No submit button here: the estimate appears on its own once three things are filled in.
- What you drank, using the counters (still needed)
- When your last drink was, including AM or PM (still needed)
- Body weight (40 to 250 kg, 88 to 551 lb) (still needed)
You will get a sober-by window, not a verdict: an honest range across how fast different bodies absorb and clear alcohol. The later edge is the one to plan around.
The short answer
Your liver eliminates alcohol at a near-constant rate of about 0.015 percentage points of BAC per hour, with a published range of roughly 0.012 to 0.020 across healthy adults.2 That is close to one US standard drink per hour. The rate does not scale with how much you drank: after a heavy night the queue is simply longer, which is why ten drinks can keep alcohol in your blood well into the next afternoon.4
Detection is a different clock. Tests that look for alcohol itself (blood, breath, saliva) go quiet when your BAC reaches zero. Tests that look for its breakdown products (urine EtG/EtS) or its long-term record (hair) stay positive long after impairment has ended.5
Detection windows by test
| Test | Typical window | What it actually tells you |
|---|---|---|
| Blood | Up to ~12 hours | Directly tracks BAC; a heavy night can keep it positive into the next morning. |
| Breath | Up to ~24 hours | Mirrors blood. Positive as long as BAC is above zero, which after a big night can be most of a day. |
| Urine (ethanol) | ~12 to 24 hours | Lags blood by an hour or two because urine pools in the bladder. |
| Urine (EtG/EtS) | ~1 to 3 days | Detects breakdown products, not impairment. Labs quote up to roughly 80 hours after heavy drinking. |
| Saliva | ~12 to 24 hours | Roughly parallels blood alcohol. |
| Hair | Up to ~90 days | Records drinking history, not current state. Used for abstinence monitoring, not impairment. |
Windows are typical figures from the sources below, not guarantees. Dose, body, hydration, and lab cutoffs all move them.
How long does alcohol stay in your blood?
Blood is where impairment lives, and it follows the elimination arithmetic directly. A BAC of 0.08, the US legal limit for driving, takes roughly four to seven hours to reach zero after absorption is complete. A 0.20 from a genuinely heavy night takes ten to seventeen. The average is close to one standard drink per hour, and the honest range is what the calculator above works with.2
Absorption adds a lag on the front end: BAC keeps climbing for 30 to 90 minutes after the last drink, longer on a full stomach, which is why the tool flags recent drinks as "still rising."3
How long does alcohol stay on your breath?
Breath alcohol is blood alcohol measured through the lungs, so the window is the same: a breathalyzer reads positive as long as your BAC is above zero, which after a heavy night can be most of the next day. Mouthwash, mints, and coffee change the smell, not the reading; alveolar air comes from your blood, not your mouth.
How long does alcohol stay in your urine?
Ethanol itself shows up in urine for roughly 12 to 24 hours, lagging blood slightly because urine pools in the bladder between voids. The tests that surprise people are EtG and EtS, which detect alcohol's breakdown products: they commonly stay positive for one to three days, and laboratories quote windows up to about 80 hours after heavy drinking.5
A positive EtG says "this person drank recently." It does not say the person was impaired at the time of the test, which is why these tests are used for abstinence monitoring rather than for measuring drunkenness.
Saliva, hair, and breast milk
Saliva tracks blood closely and is used in roadside screening in some countries; expect a window similar to breath, up to about a day after heavy drinking.
Hair is the long-memory test: EtG deposited in growing hair can record drinking for up to about 90 days. It answers "has this person been drinking these months," never "is this person drunk."7
Breast milk carries the same alcohol concentration as blood, rising and falling with it. Pumping and discarding does not clear it faster; milk re-equilibrates as long as blood alcohol is present. LactMed and the CDC suggest waiting roughly two hours per standard drink before nursing.6
Can you make it leave faster?
No. Elimination is enzyme-limited, running at the same pace whether you are asleep, exercising, or drinking espresso. The full honest treatment of every folk remedy is on the sober-up page, and the one-line version is: only time.
Never drive after drinking. If you are wondering whether you are sober enough to drive, the answer is no.
Frequently asked questions
How long does alcohol stay in your system?
As impairing alcohol in your blood: about one US standard drink per hour, so a six-drink night needs roughly six to twelve hours after the last drink to reach zero, depending on your body. As something a test can find: breath and saliva up to about a day, urine EtG tests one to three days, and hair up to about ninety days. The window depends entirely on which measurement you mean.
How long does alcohol stay in your blood?
Blood alcohol falls at roughly 0.012 to 0.020 percentage points per hour, about 0.015 on average, and the clock only starts once absorption is done. A BAC of 0.10 therefore needs somewhere between five and eight more hours to reach zero. Nothing you eat, drink, or do changes that rate.
How long does alcohol stay in your urine?
Ethanol itself appears in urine for roughly 12 to 24 hours after drinking. EtG and EtS tests, which look for alcohol’s breakdown products, stay positive far longer: commonly one to three days, and laboratories quote windows up to about 80 hours after heavy drinking. An EtG test being positive says you drank recently; it says nothing about being drunk now.
Can you speed up how fast alcohol leaves your system?
No. Elimination runs at a fixed, enzyme-limited pace. Coffee, cold showers, exercise, sweating, water, and every product marketed for the purpose leave your BAC exactly where it was; at most they change how awake you feel while you wait. Time is the only variable that matters.
How long after drinking can I breastfeed?
Alcohol leaves breast milk at the same pace as blood, roughly one standard drink cleared per two to two and a half hours for many people. Pumping does not speed this up; milk re-equilibrates with blood. The practical guidance from LactMed and the CDC is to wait about two hours per standard drink before nursing.
Why do I feel sober before my BAC is zero?
Tolerance and acute adaptation mask impairment, and feeling recovered is one of the least reliable signals your body produces. Reaction time and judgment stay measurably degraded at BAC levels where regular drinkers report feeling fine. That mismatch is precisely why this site shows ranges and never a green light.
Related tools and answers
The morning-after estimator: your night, your window, honest uncertainty.
Standard Drink CalculatorCount the night correctly first; every gram moves the window.
How to sober upCoffee, showers, food: what the evidence says about each.
How these estimates workThe Widmark formula, every assumption, and every error source, cited.
Sources
- NIAAA. Alcohol metabolism.
- Jones, A.W. (2010). Evidence-based survey of the elimination rates of ethanol from blood. Forensic Science International.
- Norberg, Å. et al. (2003). Role of variability in explaining ethanol pharmacokinetics. Clinical Pharmacokinetics.
- Cederbaum, A.I. (2012). Alcohol metabolism. Clinics in Liver Disease.
- StatPearls. Ethanol toxicity. NCBI Bookshelf.
- Drugs and Lactation Database (LactMed): Alcohol. NCBI Bookshelf.
- Pragst, F. & Balikova, M.A. (2006). State of the art in hair analysis for detection of drug and alcohol abuse. Clinica Chimica Acta.