The present invention relates to an air-cooled centrifuge comprising a rotor driven around a rotation axis by a motor and a cooling channel, which surrounds one wall of the rotor, wherein the cooling channel is provided for the air transportable in the cooling channel with an outlet opening, through which air can flow out from the centrifuge, and the outlet opening comprises a first wall, which starts at the outer periphery of the cooling channel and continues in such a way that it has an increasing distance from the rotation axis of the rotor with the simultaneously increasing rotation angle around the rotation axis of the rotor, wherein the outlet opening comprises a second wall, which starts at the outer periphery of the cooling channel and continues in such a way that it has an increasing distance from the rotation axis of the rotor with the simultaneously increasing rotation angle around the rotation axis of the rotor, so that the second wall extends as a straight line or has a curved contour, whose centers of curvature are turned away from the outlet opening.