A calculator for the duration for a certain distance from time and length of another distance. Please enter a covered distance and the time this took. Enter, for which distance the time should be extrapolated, here one kilometer is preset. The time for the new distance and the speed in kilometers per hour (km/h), meters per second (m/s), or miles per hour (mph), will be calculated. The speed is the same for both distances. In practice, it is of course hard to keep a speed, so this extrapolation is only an approximation.