Unit conversion methods and systems that use an auto-scaling algorithm to sort conversion results. A plurality of unit conversion results, which represent a conversion of an input value in an input unit, are sorted into a sorted list based on the scale of the values in the results and the sorted list is presented (e.g. displayed) to a user. In one embodiment, the sorting is done without regard to the units in the conversion results and values between zero and one are transformed before sorting.