A tool for machining holes in workpieces, in particular a fine machining tool or reamer, having - a main body having a center axis, - at least one cutting device having at least one geometrically determined cutting edge, - a clamping device by means of which the cutting device can be securely clamped to the main body of the tool, - an adjusting device which interacts with the cutting device for adjusting the machining diameter of the tool, and having - a guiding device, which comprises an elongated guiding element which interacts with an elongated guiding receptacle in such a way that the cutting device can be guided in a sliding manner perpendicular to the center axis during a displacement when the adjusting device is activated, wherein the guiding element is provided on the cutting device and the guiding receptacle is provided on the main body of the tool or the guiding element is provided on the main body of the tool and the guiding receptacle is provided on the cutting device, and wherein the guiding element and the guiding receptacle extend perpendicular to the center axis of the main body of the tool, wherein the guiding device has a single guiding element and/or a single guiding receptacle, wherein the guiding element has an elongated elevation and the guiding receptacle has an elongated recess and wherein cutting device has at least one supporting surface arranged at a distance from the guiding element or from the guiding receptacle, characterized in that the guiding element and/or the guiding receptacle has two guiding regions which are arranged at a distance from one another, wherein the cutting device has a base surface and is supported by means of a three-point contact on the main body of the tool in the region of the base surface. - a main body having a center axis, - at least one cutting device having at least one geometrically determined cutting edge, - a clamping device by means of which the cutting device can be securely clamped to the main body of the tool, - an adjusting device which interacts with the cutting device for adjusting the machining diameter of the tool, and having - a guiding device, which comprises an elongated guiding element which interacts with an elongated guiding receptacle in such a way that the cutting device can be guided in a sliding manner perpendicular to the center axis during a displacement when the adjusting device is activated, wherein the guiding element is provided on the cutting device and the guiding receptacle is provided on the main body of the tool or the guiding element is provided on the main body of the tool and the guiding receptacle is provided on the cutting device, and wherein the guiding element and the guiding receptacle extend perpendicular to the center axis of the main body of the tool, wherein the guiding device has a single guiding element and/or a single guiding receptacle, wherein the guiding element has an elongated elevation and the guiding receptacle has an elongated recess and wherein cutting device has at least one supporting surface arranged at a distance from the guiding element or from the guiding receptacle, characterized in that the guiding element and/or the guiding receptacle has two guiding regions which are arranged at a distance from one another, wherein the cutting device has a base surface and is supported by means of a three-point contact on the main body of the tool in the region of the base surface.