To provide a state estimation program in which a vehicle state is estimated from the standpoint of a driver and also to provide an information processing device.

An information processing device 1 includes: a state 103 such as during operation, temporary stopping and parking obtained by a running state estimation means which estimates a state such as running, idling and engine off as a running state of a vehicle 3 based on acceleration information 111 obtained by detecting an acceleration speed of the vehicle 3 by an acceleration sensor 12; and an operating state estimation means 104 which estimates an operating state of the vehicle 3 based on the acceleration information 111 and the running state information 112.