A heat exchanger for cooling a gas includes a gas inlet, a gas outlet, and a plurality of cooling tubes arranged between the gas inlet and the gas outlet, wherein the cooling tubes of two successive tube rows are arranged offset transversely to a flow direction of the gas. A fin having openings is provided for receiving a corresponding number of the cooling tubes. The fin has slits arranged at a distance from the openings and configured to follow an edge profile of a honeycomb-shaped hexagon, with the slits of each hexagon surrounding a corresponding one of the openings at the distance. Arranged between adjacent ones of the openings is a corresponding one of the slits at a same distance from each of the adjacent openings, with each slit having an end ending at a deformation point of the fin.