Abstract: An interchangeable-object holding apparatus for an EUV metrology system serves for holding and providing an interchangeable object, which is intended to be used interchangeably within the EUV metrology system. An interchangeable-object holder is drivably displaceable via at least one holding drive. A calibration device serves for calibrating a relative position of the interchangeable object in the interchangeable-object holder with respect to a calibration object of the interchangeable-object holding apparatus. The calibration device has a plurality of holder abutment bodies, secured to the interchangeable-object holder, and a plurality of calibration-object counter-abutment bodies, secured to the calibration object. At least one contact sensor of the calibration device serves for detecting a contact between the respective holder abutment body and the respective calibration-object counter-abutment body. An evaluation unit is in signal communication with the holder drive and the contact sensor.