Calibration device for an extruded plastic profile strand for calibrating the extruded plastic profile strand into a calibrated plastic profile comprising a calibrator body with at least one channel (34, 35, 36; 37, 37a, 37b, 37c), which extends in a movement direction and has at least one inlet and one outlet and has a cross-sectional shape perpendicular to the movement direction at the outlet, which corresponds to the calibrated external cross-section of the plastic profile to be calibrated, characterized in that the calibrated plastic profile comprises at least two complementary elements (51c, 52h, 52c, 52d; 52c, 51h, 51d, 51e; 51h, 51f, 51g, 52g; 52h, 52f, 52g, 51g; 53c, 53h, 53d, 53e) in the calibrated state on the output side, which complementary elements form a form fit in the cross section perpendicular to the movement direction, and in that the at least one channel (34, 35, 36; 37, 37a, 37b, 37c) has a cross-sectional shape perpendicular to the movement direction at the inlet in which the at least two complementary elements (51c, 52h, 52c, 52d; 52c, 51h, 51d, 51e; 51h, 51f, 51g, 52g; 52h, 52f, 52g, 51g; 53c, 53h, 53d, 53e) of the plastic profile to be calibrated are separated perpendicular to the movement direction and do not form a positive fit, and in that the at least one channel (34, 35, 36; 37, 37a, 37b, 37c) is designed from the inlet to the outlet such that the at least two complementary elements (51c, 52h, 52c, 52d; 52c, 51h, 51d, 51e; 51h, 51f, 51g, 52g; 52h, 52f, 52g, 51g; 53c, 53h, 53d, 53e) of the at least one channel are formed along the movement direction in a manner (Q1, Q2, Q3) bringing them progressively closer to each other and then together into one calibrating channel region (36; 37c) in such a way that the sections of the extruded plastic profile strand forming the at least two complementary elements (51c, 52h, 52c, 52d; 52c, 51h, 51d, 51e; 51h, 51f, 51g, 52g; 52h, 52f, 52g, 51f; 53c, 53h, 53d, 53e) are brought into form fit at the outlet by plastic and/or elastic deformation. a calibrator body with at least one channel (34, 35, 36; 37, 37a, 37b, 37c), which extends in a movement direction and has at least one inlet and one outlet and has a cross-sectional shape perpendicular to the movement direction at the outlet, which corresponds to the calibrated external cross-section of the plastic profile to be calibrated, characterized in that the calibrated plastic profile comprises at least two complementary elements (51c, 52h, 52c, 52d; 52c, 51h, 51d, 51e; 51h, 51f, 51g, 52g; 52h, 52f, 52g, 51g; 53c, 53h, 53d, 53e) in the calibrated state on the output side, which complementary elements form a form fit in the cross section perpendicular to the movement direction, and in that the at least one channel (34, 35, 36; 37, 37a, 37b, 37c) has a cross-sectional shape perpendicular to the movement direction at the inlet in which the at least two complementary elements (51c, 52h, 52c, 52d; 52c, 51h, 51d, 51e; 51h, 51f, 51g, 52g; 52h, 52f, 52g, 51g; 53c, 53h, 53d, 53e) of the plastic profile to be calibrated are separated perpendicular to the movement direction and do not form a positive fit, and in that the at least one channel (34, 35, 36; 37, 37a, 37b, 37c) is designed from the inlet to the outlet such that the at least two complementary elements (51c, 52h, 52c, 52d; 52c, 51h, 51d, 51e; 51h, 51f, 51g, 52g; 52h, 52f, 52g, 51g; 53c, 53h, 53d, 53e) of the at least one channel are formed along the movement direction in a manner (Q1, Q2, Q3) bringing them progressively closer to each other and then together into one calibrating channel region (36; 37c) in such a way that the sections of the extruded plastic profile strand forming the at least two complementary elements (51c, 52h, 52c, 52d; 52c, 51h, 51d, 51e; 51h, 51f, 51g, 52g; 52h, 52f, 52g, 51f; 53c, 53h, 53d, 53e) are brought into form fit at the outlet by plastic and/or elastic deformation.