Z4 (computer)

The Zuse Z4 is developed by the Zuse engineers and equipment digital computer, built from 2200 relay. It has a mechanical memory, which can hold 64 numbers.


The Z4 was built from 1942 to 1945 as a further development of the Zuse Z3 in Berlin. To give it more flexibility of the programming side, has made provision for the connection of several pick-up ( paper tape reader ) and Locher ( paper tape punch ). Tape were next buttons and lights the input and output medium of this computer. Shortly before completion in spring 1945, the Z4 was moved to Göttingen in the Aerodynamic Research Institute of the KWI for Fluid Dynamics. There she was completed and the first program-controlled computations could be performed. In early April 1945, she was transported to Southern Germany, they survived the ravages of war, first in a shed in rear stone in the Allgäu, later in a flour warehouse in Hopferau.

First commercial computer

1950 was the Z4 the only functioning computer in Europe. The Institute of Applied Mathematics of Professor Eduard Stiefel at the ETH Zurich in 1950 brought this from the Zuse KG repaired copy of the Z4 rental basis to Zurich. Thus, the Z4 was the first commercial computer world. It was installed a few months earlier than the UNIVAC.

The Z4 served from 1950 to 1955 as the central computer of the ETH Zurich and brought boots and insights to build his own computer ERMETH. My limited memory for intermediate values ​​had some influence on the details then at the Institute developed algorithms.

Subsequently, the Z4 was sold in 1955 near Weil am Rhein to a French defense research institute at Basel, where they 1957 a relay controlled Ferritkernspeicher received, which could save a logical information per ferrite core.


The Z4 was 1960 left to the Deutsches Museum in Munich and since 1988 part of the exhibition on computer science at the Deutsches Museum.

Comparison with other early computers

More Zuse computer

  • Zuse Z1 (1937 )
  • Zuse Z2 (1939 )
  • Zuse Z3 (1941 )
  • Zuse Z22 (1955 )