A towel dispenser includes a housing, a sensor, and a motor assembly that causes in response to a hand: a leading edge of the toweling to be extended from the housing a multiple of a predetermined unit length (PUL), optionally plus a further extent that is less than PUL; and then to be retracted. The motor assembly ceases retracting based on sensing the leading edge of the toweling. PUL is set in a length learn sequence by: retracting the toweling until a leading edge of the toweling is sensed; advancing the toweling a preset extended length greater than at least a distance between immediately adjacent lines of perforations in the toweling; retracting the toweling until a leading edge of the toweling is sensed while measuring a length by which the toweling is retracted; and determining the difference between the preset extended length and the measured retracted length.