A turbine for a turbocharger comprising: a turbine housing defining a volute with a substantially annular outlet opening, the outlet opening extending axially between a first contour line and a second contour line of the volute; a turbine wheel; and an adjusting ring, rotatable about the turbine axis, which is arranged in the turbine housing radially between the volute and the turbine wheel, the adjusting ring having a radially outer lateral face and a radially inner lateral face, wherein the adjusting ring comprises a flow channel between a radially outer first peripheral opening and a radially inner second peripheral opening, the first peripheral opening extending axially between a first surface line and a second surface line of the radially outer lateral face, and wherein the outlet opening is fluidically coupled to the turbine wheel by the flow channel, characterized in that the first contour line and the second contour line each extend at different axial positions in a circumferential direction such that the outlet opening is arranged axially along different positions with respect to the turbine axis, first surface line and second surface line each extend at different axial positions in the circumferential direction such that the first peripheral opening is arranged on the radially outer lateral face along positions which axially differ with respect to the turbine axis, so that during a rotation of the adjusting ring, the outlet opening and the first peripheral opening are adjusted relative to each other in such a way that an overflow cross section between the outlet opening and the first peripheral opening is variably changeable. a turbine housing defining a volute with a substantially annular outlet opening, the outlet opening extending axially between a first contour line and a second contour line of the volute; a turbine wheel; and an adjusting ring, rotatable about the turbine axis, which is arranged in the turbine housing radially between the volute and the turbine wheel, the adjusting ring having a radially outer lateral face and a radially inner lateral face, wherein the adjusting ring comprises a flow channel between a radially outer first peripheral opening and a radially inner second peripheral opening, the first peripheral opening extending axially between a first surface line and a second surface line of the radially outer lateral face, and wherein the outlet opening is fluidically coupled to the turbine wheel by the flow channel, characterized in that the first contour line and the second contour line each extend at different axial positions in a circumferential direction such that the outlet opening is arranged axially along different positions with respect to the turbine axis, first surface line and second surface line each extend at different axial positions in the circumferential direction such that the first peripheral opening is arranged on the radially outer lateral face along positions which axially differ with respect to the turbine axis, so that during a rotation of the adjusting ring, the outlet opening and the first peripheral opening are adjusted relative to each other in such a way that an overflow cross section between the outlet opening and the first peripheral opening is variably changeable.