If you hold a valid U.S. driver’s license, you can drive in Germany for up to six months (from the date of your arrival) without acquiring a German driver’s license. If you will be residing in Germany for longer than six months but less than one year, you can apply for a six-month extension to continue using your existing license.
American citizens resident in Germany for one year or more must be in possession of a German license six months after entering the country, if they wish to continue driving. A U.S. license holder requiring a German license must contact a local German driving school which will provide information on the necessary paperwork and register the applicant for testing.
The German government has reciprocity agreements with a number of US states. Depending on the kind of agreement, holders of a US driver‘s license from these states can be exempted from the practical test (behind-the-wheel) or both the practical and theoretical (written) tests for obtaining a German driver’s license. Check out this PDF from the American Chamber of Commerce in Germany to learn which states have full or partial reciprocity agreements with Germany and how to obtain a German driver’s license.
For more general information about driving in Germany, please visit our website at http://germany.usembassy.gov/acs/driving_in_germany/