Abstract: A plate brake tester for testing the brakes of a motor vehicle, comprises two pair of tread plates one beside the other, each of said tread plates having a measuring device for measuring the force exerted on the tread plate, a processing unit for processing measuring signals provided by the measuring devices and a display for displaying the measuring results. The plate brake tester comprises a weighing device for determining the weight of the front axle and the rear axle of the vehicle, respectively. The processing unit is adapted to compute the braking retardation from the measured brake forces and the total weight of the vehicle. The plate brake tester computes the brake force ratio front axle/rear axle from the measured brake forces and the dynamic weight ratio front axle/rear axle from the computed braking retardation, the wheelbase of the vehicle, the height of the center of gravity of the vehicle and the measured weight of the front axle and the rear axle, respectively.