A method for weighing masses on a conveyor system (18) on which the masses to be weighed are advanced in horizontal direction and which includes a conveyor section (24) that is limp in a vertical bending direction, including the steps of continuously measuring the weight force that acts upon the limp conveyor section (24) while the masses are advanced on this conveyor section, recording a force/displacement function that indicates the weight force as a function of the distance traveled by the conveyor system (18), and calculating the mass flow rate of the conveyor system by evaluating the force/displacement function.