An information processing device includes, a processor; and a memory which stores a plurality of instructions, which when executed by the processor, cause the processor to execute, acquiring images which includes a target object, and the images captured by a plurality of cameras on a time series basis; calculating a plurality of distance from the plurality of each cameras to a target object by using the images; and correcting, in a case where the target object has reached a predetermined x-y plane and a difference in an area of the target object between the images is equal to or less than a predetermined first threshold, the distance that has been calculated to a distance from the cameras to the x-y plane.