BAC Calculator · Practical guide
How Long Does It Take to Sober Up After Drinking?
Time is the only thing that lowers blood alcohol — here is how much of it you actually need.
At a glance
The Short Answer
Blood alcohol concentration falls by about 0.015% per hour for most people, regardless of what you do. Sobering up from the legal limit of 0.08% takes roughly 5 hours and 20 minutes from your last drink — and from 0.10%, about 6 hours and 40 minutes. The calculator above applies this rate to your drinks, weight, gender, and elapsed time.
Interactive tool
BAC Calculator
Enter your own values, then compare the result with the examples below.
One standard drink contains approximately 14 grams of pure alcohol.
Alcohol Metabolism Estimate
Time to Sober by Starting BAC
| Estimated BAC | Hours to Reach 0.00% | Hours to Reach 0.02% |
|---|---|---|
| 0.04% | ~2 h 40 m | ~1 h 20 m |
| 0.06% | ~4 h | ~2 h 40 m |
| 0.08% | ~5 h 20 m | ~4 h |
| 0.10% | ~6 h 40 m | ~5 h 20 m |
| 0.15% | ~10 h | ~8 h 40 m |
The second column matters in practice: even well below the legal limit, impairment lingers, and some states penalize driving at lower BAC levels.
Nothing Speeds It Up
Coffee, cold showers, exercise, and a big meal after drinking may make you feel more alert, but none of them removes alcohol from your blood. Your liver metabolizes roughly one standard drink per hour, and that rate is essentially fixed. Sleeping does not pause the clock — but it does not speed it either; you simply wake up later on the same curve.
Estimating Your Own Timeline
The Widmark formula behind the calculator estimates your peak BAC from your drinks (14 grams of alcohol each), body weight, and gender, then subtracts 0.015% for every hour since your first drink. A 180-pound man who has 3 beers over 2 hours sits around 0.046%, needing roughly 3 more hours to reach zero. Individual metabolism, food, and medications shift the real number — when in doubt, wait longer or do not drive.
Frequently Asked Questions
Does drinking water or coffee lower BAC faster?
No. Water helps with hydration and coffee with alertness, but neither changes the roughly 0.015% per hour metabolism rate. Only time lowers BAC.
Can I still be over the limit the next morning?
Yes. Reaching 0.15% at midnight means you are still near 0.05-0.06% at 8 a.m. Heavy late-night drinking routinely produces impaired mornings.
Why does the estimate differ from a breathalyzer?
The Widmark formula is a population average. Food, medications, body composition, and individual metabolism all move real BAC, so treat the estimate as a floor, not a guarantee.
Does eating before drinking slow sobering time?
Food slows absorption, so your peak BAC arrives lower and later — but total sobering time from a given peak is unchanged. You sober up at the same rate from wherever you peak.