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.