Method and filling device for filling a container with a filling product, in a beverage filling system, wherein the method comprises: determining one or more changeable influence variables which influence a target variable of the filling process, a filling level and/or a filling volume; receiving the influence variables by means of a control apparatus; calculating at least one output variable from the received influence variables by means of a calculation model of the control apparatus; and filling the container as a function of the at least one output variable.