Konrad Zuse. Biography. Contributions. Zuse-Companies. Z3r. Tour-Zuse-Computer. Z23 Crosses Altlantic. Early Computers. Neumann vs Konrad Zuse. Impressum and Contact. Professor Dr.-Ing. habil.
Horst Zuse


The development of the computer Z23 began in 1958 by the Zuse KG and the first Z23 was delivered in 1961.

The Z23 was a further development of the approved Z22 in transistor technique. The Z23 decreed about a magnetic drum, a ferrit core memory and expensive periphery.

The logic structure of the Z23 was similar to the Z22. The Z23 was delivered with an ALGOL 60 compiler.

The user of the Z23 were almost the same as with the Z22. Applications areas were machine building, ship building, electrical engineering, electronics, hydro and gas dynamics, reactor physics, ballistics, geodesy, optics, energy supply, traffic technique, mining, administration, government, universities, chemical production, boiler construction.

The Zuse KG delivered 98 machines till 1967. The Z23 computer was a machine consisting of 2700 transistors and more than 600 diodes. It was a very successful machine for the Zuse KG. The price of the Z23 was 200 000 DM in 1961.

The next picture shows a computer center with the Z23.

The Story of Restoring the Historical Zuse Z23 Computer by the Konrad Zuse Schule crossing the Atlantic to Mountain View.

Name of Machine
Z23 (from 1961)
Transistors and diodes.
Ca. 140.000 Hertz generated by the drum.
Arithmetic Unit
Fixed point and floating point, 38 bits.
Average calculation Speed
Fixed point: Addition 0,3ms, Multiplication 13ms, Division 13ms, Floating point: Addition 10,6ms, Division 20ms.
Punchtape and teletype writer.
Punchtape and teletyp writer.
Word Length
38 bits
Ca. 2900 transistors and ca. 7700 diodes.
Ferrit core with 248 words and each of 38 bits. Drum with 8192 words each 38 bits.. Z23VK with a ferrit core of 8192 words.
Power Consumption
Ca. 4000Watt
Ca. 1000 KG
Area of Application
Areas of application: Constructional engineering, machine building, shipbuilding, electronics, hydro dynamics, gas dynamics, nuclear reactor physics, ballistics, surveying, optics, power supply, traffic control, mining, public service, universities, chemical production, optics. Compilers for German formula code and for ALGOL 60 are available.
From 180.000 DM
Zuse-Computer (English)
Zuse-Computer (German)
Konrad Zuses Work on a DVD
Mostly wide spread transistor computer in Germany. The Z23 was upward compatible related to the Z22.
From left to right: The leaflet of the Z23. The ferrit core memory. The drum with 6000 rotations a minute. The Z23 in the Compuuter Museem History Center in Mountain View / California / US.

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