A simple technique is used to determine the degree of fragmentation during the fluidized bed combustion of biochar pellets. From the analysis of the evolution of the overall resistance of combustion of batches of particles, composed alternatively by robust and fragile particles, kinetic and diffusive data for both types of particles were obtained. Subsequently, through the obtained combustion information, the degree of fragmentation of the fragile particles was determined. The experiments were carried out for bed temperatures of 700 and 800 degrees C, using Acacia dealbata char pellets.