What requirements apply to the driving license when renting a car in Germany?

Documents:

At the time of renting, all drivers must have a valid driving permit/driver's license (digital licenses are not accepted) as well as an ID card or passport. Non-English driver's licenses issued in a country outside Europe must be presented in combination with an English-language international driver's license. Driving licenses from non-EU countries are valid for making a rental up to six months from the stamp date in the renter's passport. After the six months have elapsed, a driver's license issued in the EU is required by law.

Age:

All drivers must be at least 21 years old to rent a vehicle. Customers from 21 to 24 years of age may rent vehicles from the following classes: Compact to standard, five-seater minivan, small off-road vehicle/SUV (medium and standard), and van. Customers 25 years of age and older may rent vehicles from any vehicle class.