Sober Time Calculator
From a current blood alcohol estimate, see roughly how long until you reach 0.00 and how long until you would fall under 0.08.
How it works
hours to 0.00 = BAC ÷ 0.015 · hours to under 0.08 = max(0, (BAC − 0.08) ÷ 0.015)
Alcohol leaves the bloodstream at a fairly steady average pace of about 0.015 percentage points of BAC per hour, and nothing safely speeds that up — the liver does the work on its own schedule. Dividing your current BAC by 0.015 gives a rough number of hours until you reach zero. This is an average only: real elimination rates vary substantially with genetics, liver health, sex, food and how much you drank, so the true time can be longer than the estimate. Treat it as general information, never as a green light.
Worked example
Starting from a BAC of 0.08%: time to 0.00 = 0.08 ÷ 0.015 = 5.33 hours, about 5h 20m. Since you are already at 0.08, the time to fall under 0.08 is essentially zero, but you are still legally impaired at that level.
Sources: NIAAA — Alcohol metabolism and BAC
Frequently asked questions
Can I use this to decide if I am safe to drive?
No — absolutely not. This is an average estimate that can understate how long alcohol stays in your system, impairment often begins below any legal limit, and the only safe amount of alcohol before driving is none. If you have been drinking, do not drive.
Can I sober up faster with coffee or a cold shower?
No. Only time removes alcohol from your blood. Coffee, water, food, exercise and cold showers may make you feel more awake, but they do not change your BAC or your actual impairment.
Why do people sober up at different rates?
The 0.015-per-hour figure is a population average. Liver enzyme activity, genetics, sex, body composition, food in the stomach and regular drinking habits all shift the real rate, so two people at the same BAC can take noticeably different times to clear it.
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Educational estimate, not medical advice — for clinical decisions consult a healthcare professional.