AbstractThe wear of cutting tools in mechanised tunnelling is closely linked to the abrasiveness of the present subsoil. Therefore, most of the models used for wear prediction take an abrasiveness index into account. The most common index used for hard rock is the Cerchar Abrasiveness Index (CAI); whereas such a standard does not yet exist for soil. Both the literature research and the results of calculation examples presented in the article show that significantly more practical models are currently available for wear prediction in hard rock. One reason for this is that far more wear‐relevant influencing factors have to be quantified for soft ground. Another reason is that the scientific studies concerning this topic only started in the course of mechanised tunnelling. Since especially the calculations carried out for low‐abrasive rocks differ widely among the different models for tool life, further research is needed also for wear prediction in hard rock