The invention relates to a coupling for releasably connecting pipes or pipe-like elements in a fluid-tight manner, having a first coupling part and a second coupling part which are connectable via a screw nut or the like, wherein the coupling parts are each provided with a radially outwardly extending flange and the flanges have end faces which are provided with a profile for sealing off the coupling, wherein the profile comprises at least one circumferential groove and at least one circumferential protrusion engaging in the groove, said groove and protrusion forming a fluid-tight seal between one another in the coupled state, and wherein the protrusion comprises a lateral sealing face which has an outwardly bulging shape in cross section, and wherein the groove has a corresponding lateral counterpart sealing face that is inclined with regard to the longitudinal axis of the coupling, such that, in the installation position, the sealing face of the protrusion is pressed against the counterpart sealing face of the groove.