Visit the American Automobile Association website to view/print the driver's permit application.
International Driving Permit
"Geographical Areas Which Honor International Driving Permits (Convention on Road Traffic, United Nations, Geneva 1949) as of January, 2009."
Select country details from the application:
ARGENTINA***
BRAZIL (Inter-American Driving Permit Only)
BOLIVIA*/***
CHILE***
COSTA RICA*/***
COLOMBIA*/***
EL SALVADOR*/***
FRANCE (INCLUDING FRENCH OVERSEAS TERRITORIES) ...i.e. French Guiana...
GUATEMALA***
GUYANA
HONDURAS*/***
MEXICO*/***
NICARAGUA*/***
PANAMA*
PARAGUAY***
PERU***
SURINAME
URUGUAY (Inter-American Driving Permit Only)
VENEZUELA***
*Not party of 1949 Convention: International Driving Permit Honored.
**U.S. driver's license and International Driving Permit recognized on presentation to local police and payment of Special Registration Fee upon arrival.
***Geographical Areas Which Honor Inter-American Driving Permits (Convention on Regulation of Inter-American Motor Vehicle Traffic, Organization of American States, Washington, D.C. 1943) as of January, 2009. If you intend to drive in the following countries, be sure to check INTER-AMERICAN DRIVING PERMIT box page 1: Brazil and Uruguay.
I ultimately bought both permits, Inter-American Driving Permit and International Driving Permit, to cover all countries when preparing for a ride in South America in 2008. When I rode Central and South America in 2012-2013 I took the expired Inter-American Driving Permit. On both trips I was never asked to produce either driving permit.
In 2008 while traveling in Nicaragua I was stopped for crossing a double yellow line. The policeman questioned the validity of my New Jersey drivers license. He pointed to a blank corner of the license as if there should be something printed there...not the case. I produced my title, importation and insurance paperwork, then for good measure both of my drivers permits. That ended the question of the validity of my New Jersey drivers license. He berated my weak Spanish skills and tried to intimidating me with the steps I would have to take to pay the ticket, go to a bank in Managua, pay the fine, etc. My driver's license was put into an accordion folder and removed several times. I kept say OK, which is not what he wanted. As more vehicles were being pulled over he lost interest in trying to get a bribe and let me go.
The next day in Costa Rica I made the same mistake and that cop spoke perfect English, so I couldn't play dumb. He made it clear, $80 to pay the ticket in town or $40 and the problem goes away. I should have talked him down, but was a bit nervous and paid the bribe. Live and learn.
If I plan another trip in Central and South America, I would go to AAA and buy both permits. The cost is low and give you peace of mind, and maybe the permits will get you out of a jam. Look at it as the cost of adventure.