Abstract: A system for calculating the operating distance range remaining for a vehicle. The system includes a driver input sensor for sensing predetermined vehicle operating condition data, an energy storage sensor for sensing energy storage capacity data of a corresponding energy supply mechanism, a controller in communication with the driver input sensor and the energy storage sensor. An executable range calculation software program is stored in the memory of the controller which uses sensed vehicle operating condition data from the driver input sensor and sensed energy storage capacity data from the energy storage sensor to determine range by determining a mean of energy storage capacity data, determining a slope of the energy storage capacity data, determining an intercept of the energy storage capacity data, and applying a least square linear regression to the determined mean, determined slope and determined intercept to find the remaining range.