Abstract: A method and a device for continuous or semi-continuous casting of metal. A primary flow (P) of hot metallic melt supplied into a mold is acted upon by at least one static or periodically low-frequency magnetic field to brake and split the primary flow and form a controlled secondary flow pattern in the non-solidified parts of the cast strand. The magnetic flux density of the magnetic field is controlled based on casting conditions. The secondary flow (M, U, C1, C2, c3, c4, G1, G2, g3, g4, O1, O2, o3, o4) in the mold is monitored throughout the casting and upon detection of a change in the flow, information on the detected change monitored flow is fed into a control unit (44) where the change is evaluated and the magnetic flux density is regulated based on this evaluation to maintain or adjust the controlled secondary flow.