© 2021 Elsevier LtdThis paper presents the studies carried out to estimate the grinding energy of vertical roller mills via breakage test. An extensive laboratory and pilot scale test work was performed. In the first step, breakage characteristics of eight samples having different competence were determined by piston-die tests. Then, the samples were subjected to a size reduction process using a pilot scale vertical roller mill. Feed size, product size and energy data from pilot scale grinding tests were evaluated with material characterization tests. Based on energy-size reduction models proposed in the literature, equations were derived to estimate the grinding energy of the vertical roller mill by using the size and piston-die test data.