INFORMATION PROCESSING DEVICE FOR VEHICLE, AND INFORMATION PROCESSING SYSTEM

An information processing device for a vehicle includes one or more processors configured to execute acquiring vehicle driving force that is driving force of the vehicle, acquiring front-rear acceleration that is an actual measurement value of acceleration along a front-rear axis of the vehicle from an acceleration sensor mounted on the vehicle, acquiring a slope at each point of a road on which the vehicle travels, and estimating an estimation value of total weight of the vehicle, when the vehicle travels at the point where the slope is acquired, based on the vehicle driving force at the point, the front-rear acceleration at the point, and the slope at the point.