Information providing device has: travelling route searching section searching for a travelling route; and power consumption amount calculating section calculating a total power consumption amount. The power consumption amount calculating section has: first calculating section that refers to travel information correlated with a first unit area that belongs to the searched travelling route and calculates each first power consumption amount consumed to travel in the first unit area; second calculating section that refers to weather information forecasted for each second unit area that belongs to the searched travelling route, predicts setting temperature of an air conditioner and calculates each second power consumption amount consumed when the air conditioner into which the predicted setting temperature is inputted is operated during the travel in the second unit area; and totalizing section that calculates the total power consumption amount on the basis of the first and second power consumption amounts.