A vehicle speeding alert system is implemented on a GPS enabled wireless device in communication with a wireless network. The alert system periodically determines the speed of a vehicle by determining the speed of the wireless device carried therein, using GPS signals received by the wireless device. For example, speed can be calculated by dividing a certain distance that the wireless device travels by the time it takes to travel that distance. The vehicle's speed is then compared to the speed limit of the roadway on which the vehicle is traveling. The speed limit is determined by comparing the wireless device's location to map data relating to the geographic area around the location. The map data may be stored on the wireless device, or obtained from a map database accessible over the network. If the vehicle speed is above the speed limit, a notification or alert is issued.