Traffic jams and congestions have bad effects on drivers and the whole community. Mostif not allroute planning systems focus on finding the optimal/fastest route for its users. Users might be advised to pass through a congested road section if it will take less time to traverse than its alternatives. This approach ignores the negative effects of congestion on both of the individual and the whole community. Instead of focusing on giving each user the fastest route to his destination, this papers aims to develop a model that would be optimal to the whole community. The ultimate objective of the OnTraJaCS is to give all registered vehicles route recommendations that would minimize congestions when they are executed simultaneously. This is achieved by minimizing congestion over the whole map even if some trips will take longer path in order to avoid congestion formation. OnTraJaCS uses Web Ontology to detect and predict congestion and it uses Java to simulate and evaluate possible plans. Simulation results proved that the OnTraJaCS is able to find optimal plans in accordance with the desired criteria and hence fulfilling its objective, with a slight increase in average trip time.