Dear Visitor of my website,
On the corresponding German page, you will find a blood alcohol calculatur which will tell you exactly, how much alcohol you must have consumed, if your blood alcohol (Promillewert) is know. Just go there, and fill in the relevant numbers. Since I am in the project of programming a mobile website for better convenience, it will take some time before I can put the blood alcohol calculator here in English language.
In the mean time, feel free to use the German Version of the calculator.
Dr. M. Junker