Abstract: The present invention relates to a measuring unit (10) for in-process measurement during a machining operation on machine tool, in particular a grinding machine comprising at least a wheel head arranged at a headstock, comprising a measuring head (14), which is movable between a rest position and a measuring position, and means for moving the measuring head between the rest position and the measuring position. The measuring unit (10) is configured such that the rest position and the measuring position of the measuring head (14) are infinitely adjustable by a user by controlling the movement of the measuring head (14) between the rest position and the measuring position.