The invention relates to a heat exchanger comprising first fluid inlets, first fluid outlets, second fluid inlets and second fluid outlets. Each of the first fluid inlets, the first fluid outlets, the second fluid inlets and the second fluid outlets are arranged on four different sides of a heat exchanger core. A manifold covers one of the four different sides of the heat exchanger core, wherein a first sidewall of the manifold is arranged at an angle smaller than 90 degree to the one side of the heat exchanger core which is covered by the manifold. An edge of the heat exchanger core between the one side of the heat exchanger core which is covered by the manifold and a neighbouring side of the four different sides of the heat exchanger core forms a common weld line with a connecting edge of the first sidewall of the manifold. The invention also relates to a method for manufacturing a heat exchanger comprising a heat exchanger core and a manifold.