A GPS speedometer comprising: a housing; a circuit board located in the housing; a microprocessor located on the circuit board; a GPS module located on the circuit and in signal communication with the micro-processor; a GPS antenna located on the circuit board and in signal communication with GPS module; and a readable speedometer display located on the housing and in signal communication with the microprocessor, where the readable speedometer display is configured to display the current speed of the vessel or vehicle calculated by the microprocessor based on data from a global positioning system. A GPS speedometer system comprising: a vessel, the vessel comprising an instrument panel; a GPS speedometer located on the instrument panel, the GPS speedometer comprising: a housing; a circuit board located in the housing; a microprocessor located on the circuit board; a GPS module located on the circuit and in signal communication with the micro-processor; a GPS antenna located on the circuit board and in signal communication with GPS module; a readable speedometer display located on the housing and in signal communication with the microprocessor, where the readable speedometer display is configured to display the current speed of the vessel or vehicle calculated by the microprocessor based on data from a global positioning system; and a global positioning satellite in signal communication with the GPS antenna.