People often want to know how long alcohol will remain in their body after they stop drinking. What's interesting about this is that while people absorb alcohol in very different ways and at very different speeds, the excretion of alcohol occurs exactly the same from person to person.
If you have a blood alcohol level of .15, which is just about two times the legal alcohol limit, to be considered drunk. It will take 10 hours for you to actually have no alcohol left in your body. So our bodies excrete alcohol in several different ways. About 10% of the alcohol in your body will be excreted through breath and through perspiration. And the rest will be excreted over time through urine. But, again, everyone metabolizes alcohol at the same rate, which is at .015 blood alcohol concentration per hour.
So, again, if you have a blood alcohol level of .15, which is a very high alcohol level, it will take 10 hours. If it's half of that, it will take five hours. So it is predictable how long it will take for alcohol to actually leave your body.