Abstract: Method of measurement of the total length of a yarn formed winding material (3) running onto a wound package (1), in particular a yarn web running onto the winding beam of a winding machine. During continuous winding operation, the length is ascertained by means of a measuring roll (2) over which the material to be wound (3) is guided. During acceleration and braking procedures, slippage occurs between the material to be wound (3) and the measuring roll (2). On occurrence of slippage, the system of measurement is changed, and the length of the wound package is determined from the rotational speed of the wound package (.omega..sub.w) and the circumference of the wound package (1). The circumference of the wound package (1), as well as the increase of the wound package circumference per rotation of the wound package, are ascertained during continuous winding operation.