The following is true for all Caliber, Magnum, and Nitro, but only some Dakota, Durango, and Ram Pickup (the ones with immobilizer system - which is noted by a security light on dash which goes away when you put a working key in ignition.) If you have two unique working keys that start the engine when turned in ignition then you can add more keys yourself. Programming tranponders programs remotes.
If you have a Dakota, Durango, or Ram Pickup without immobilizer system (no security light on dash) then this is compatible but not the exact replacement. But if you order it for that then if you have one working remote then you can add more yourself.
In the first case if you don't have 2 working keys then you'll need an automotive locksmith to perform programming by scan tool.
This remote's FCC ID is KOBDT04A, possible part numbers on your old remote are 05175786AA, 05175786AB, 05179513AA, 56038751AE, 56038751AH, 05135670AA, and 68001705AA. Remote is tested for correct transponder and proper signal before it ships.