International drivers license

Been there, done that multiple times, and I was never asked for an international driver's license, just my Texas drivers license and passport. I normally rent from Hertz in Brussels (Excelsiorlaan or Brussels airport) and I have been very pleased with them - reservation in order, no hidden charges. They even bought me a coke once from the machine outside the office when I didn't have any change!

On the topic of hidden charges, be cautious about renting at Schiphol airport. They charged my credit card an extra 500 euro deposit that was never mentioned in my rental agreement, and I had never experienced this when renting in Belgium. It was eventually credited back when I returned the car, but took a big chunk out of my planned extra spending money. I tried other rental counters there at the airport, but was told they all have this charge at the Schiphol location. Also had problems on the return when they refused to inspect the car while I was there and said they would bill me later if they found any damage. Oh, good! I go to Belgium annually to visit family and fly into Amsterdam or Brussels, and I will never again rent a car at Schiphol.

There is no International Drivers License - if you come across it on line it is a scam.

The requirement in many countries is an International Driving Permit; in the US it is available at the AAA, in Canada at the CAA.

There is not a requirement for an IDP in the Netherlands.

It is always a very good idea to have an International Drivers Permit, even when not required. At times there can be confusion about your state license and you might be asked for an IDP by the rental agency. Or the police if there is an incident. State licenses are all different and can sometimes be confusing about expiration dates (Illinois used to renew with just a sticker with no date on it). I was once asked for an IDP in Britain of all places.