Stepped reckoner
(重定向自Stepped drum)
![Replica of Leibniz's stepped reckoner in the Deutsches Museum. ... it is beneath the dignity of excellent men to waste their time in calculation when any peasant could do the work just as accurately with the aid of a machine.— Gottfried Leibniz[1]](/uploads/202502/13/Leibnitzrechenmaschine5956.jpg)


The step reckoner (or stepped reckoner) was a digital mechanical calculator invented by the German mathematician Gottfried Wilhelm Leibniz around 1672 and completed in 1694. The name comes from the translation of the German term for its operating mechanism, Staffelwalze, meaning 'stepped drum'. It was the first calculator that could perform all four arithmetic operations.