I would like to know if I can drive in Brazil on a International driver license issued in Australia.?

I am an Australian and Brazilian resident.
My husband is Australian resident.

Foreign driver's licenses can be used for up to six months in Brazil in combination with an official translation into Portuguese stamped by the traffic authority DETRAN of the state where you are living. In case you use an International driver's license it's good to get an official translation into Portuguese of it and a stamp from the DETRAN too, because usually the International driver's license is not in Portuguese.

If you stay more than six months in Brazil you have to apply for a temporary driver's license for foreigners, valid for one year. In case you are still waiting for your ID card, temporary driver's license can be extended for another year. You have to apply for the license at the office of the local state's traffic authority DETRAN.

For the temporary driver's license for foreigners you need the following documents:

Passport (original + photocopy of the page with the personal data)
Your national driver's license (original + photocopy)
Official translation of your national driver's license (original + photocopy)
Result of the medical exam (from a doctor indicated by the DETRAN)
Proof of residence in Brazil (original + photocopy of phone or electricity bill)
CPF (original + photocopy) if you already have one

i dont know sorry

If you are going to rent a car you only need the international drivers license. If you have your own car, follow the procedures described by Meg.