The Allround Shake grader is designed to grade potatoes according to the square size. The potatoes are fed to the top of the machine on to the top sieve. The sieves in the machine shake in sequential frequencies, which causes the potatoes to move along on the sieves. The movements of the sieves is caused by the motor on the front side of the machine. This motor drives a crankshaft. The crankshaft causes the shaking of the sieves. The motor of the machine has a computer controlled frequency inverter, which causes the sieves to shake in several sequential frequencies.