This work investigates how austenite stability and phase composition varies across multiple carbon contents for a cemented carbide with a steel binder alloyed with nickel, chromium and molybdenum. The results are compared with predictions done by thermodynamic calculations and property models designed to predict the austenite stability for steel. It is found that it is possible to predict the martensite fraction in the metallic binder with reasonable accuracy. Phase identification by electron diffraction showed that mixed carbides of the form M₂₃C6 and M₇C₃ can be found in the microstructure and that these are enriched in chromium and depleted in nickel.