The McLaren M23 was designed by Gordon Coppuck, with input from John Barnard, and built by the McLaren team. It was a development of the McLaren M16 Indianapolis 500 car. A Ford Cosworth DFV engine was used, which was prepared by specialist tuning company Nicholson-McLaren Engines. This helped push the DFV's horsepower output to around 490 bhp.

A total of 13 chassis were built, with serial numbers 1 to 12 and 14. No number 13 chassis was built, as it was deemed to be unlucky.