A computer-implemented method for providing traffic information via a navigation module onboard a moving vehicle, comprising the steps of: obtaining geolocalization data of the vehicle; identifying the closest traffic light ahead the vehicle; retrieving, from a remote traffic light server, operational information on the identified closest traffic light; processing the operational information to determine an optimal speed at which the vehicle should move to arrive at the closest traffic light when it is at green phase; and outputting the optimal speed via a user interface of the navigation module.