The following policies are for passengers traveling in economy class, and are not top tier frequent flyer members for flights within the United States, the US Virgin Islands, Puerto Rico and Canada:
Free Baggage Allowance- Your first checked in bag is $25, your second is $35 with a weight allowance of 50lbs (23kg) per bag, and an additional 40lbs maximum of carry on luggage.
For Brazil and Asia, American Airlines permits 2 bags weighing a maximum of 50lbs each for free (except Brazil which allows for a maximum of 70lbs each). American is assessing a $50 fee for the second checked bag for Europe and India.
Excess baggage fees for extra/oversized/overweight luggage start at $50 and can run up to several hundred dollars. If it weighs over 100lbs it will not be accepted and you will need to contact cargo for freight charges.
American Airlines policies regarding checking strollers, car seats, mobility devices and sports equipment.