A winding layer pitch compensation for an air-core reactor which has at least two radially spaced apart concentric winding layers, includes a first set of strip-shaped star sheets, each of which is configured to be arranged radially below or above the winding layers and which are provided with at least one receiving slot along an edge extending from that edge, a second set of strip-shaped compensation sheets, each of which is provided with at least one insert slot along an extending from another edge, where a compensation sheet can be inserted into each receiving slot of a star sheet in a formfitting manner, where the star sheet engages into the insert slot of the compensation sheet in a formfitting manner, and where the slot depths of at least two receiving slots of the set of star sheets are different.