Clamping device, in particular for clamping workpieces for machining, comprising a reference plane plate which has a planar clamping surface, which defines a reference plane, and at least two clamping openings with walls, on which at least one reference surface is respectively formed, the clamping device serving to clamp a clamping plate which has a planar base surface which can be placed on the clamping surface, and comprising at least two clamping and positioning bolts associated with the clamping openings and respectively comprising a positioning surface associated with the reference surfaces, and comprising a tightening device which is equipped to apply an axial force (F ax) and a superimposed radial force (F rad) to the clamping and positioning bolts, wherein the base surface of the clamping plate can be pressed against the clamping surface of the reference plane plate by means of the axial force (F ax), and the clamping and positioning bolts with their positioning surfaces can be pressed against the reference surfaces by means of the radial force (F rad), wherein the tightening device has two clamping jaws and a clamping means, wherein a force transmission surface is provided on one of the clamping jaws for each clamping and positioning bolt, wherein each clamping and positioning bolt has a force receiving surface for interacting with one of the force transmission surfaces, wherein the force transmission surfaces of the clamping jaws can be brought into contact with the force receiving surfaces of the clamping and positioning bolts and by this means the axial forces (F ax) and the radial forces (F rad) can be applied to the clamping and positioning bolts, wherein the clamping means and the clamping jaws can be displaced along a single, defined movement axis, characterized in that the clamping device a first set of clamping openings for receiving the clamping and positioning bolts of a first clamping plate with first distances between the clamping and positioning bolts, and has a second set of clamping openings for receiving the clamping and positioning bolts of a second clamping plate with second distances between the clamping and positioning bolts, wherein the first distances and the second distances are different, wherein both clamping jaws respectively have four force transmission surfaces, wherein two first force transmission surfaces of each clamping jaw can respectively be brought into contact with the force receiving surfaces of the clamping and positioning bolts of the first clamping plate when the clamping and positioning bolts of the first clamping plate are engaged with the first set of clamping openings, and two second force transmission surfaces of each clamping jaw can respectively be brought into contact with the force receiving surfaces of the clamping and positioning bolts of the second clamping plate when the clamping and positioning bolts of the second clamping plate are engaged with the second set of clamping openings. the clamping device serving to clamp a clamping plate which has a planar base surface which can be placed on the clamping surface, and comprising at least two clamping and positioning bolts associated with the clamping openings and respectively comprising a positioning surface associated with the reference surfaces, and comprising a tightening device which is equipped to apply an axial force (F ax) and a superimposed radial force (F rad) to the clamping and positioning bolts, wherein the base surface of the clamping plate can be pressed against the clamping surface of the reference plane plate by means of the axial force (F ax), and the clamping and positioning bolts with their positioning surfaces can be pressed against the reference surfaces by means of the radial force (F rad), wherein the tightening device has two clamping jaws and a clamping means, wherein a force transmission surface is provided on one of the clamping jaws for each clamping and positioning bolt, wherein each clamping and positioning bolt has a force receiving surface for interacting with one of the force transmission surfaces, wherein the force transmission surfaces of the clamping jaws can be brought into contact with the force receiving surfaces of the clamping and positioning bolts and by this means the axial forces (F ax) and the radial forces (F rad) can be applied to the clamping and positioning bolts, wherein the clamping means and the clamping jaws can be displaced along a single, defined movement axis, characterized in that the clamping device a first set of clamping openings for receiving the clamping and positioning bolts of a first clamping plate with first distances between the clamping and positioning bolts, and has a second set of clamping openings for receiving the clamping and positioning bolts of a second clamping plate with second distances between the clamping and positioning bolts, wherein the first distances and the second distances are different, wherein both clamping jaws respectively have four force transmission surfaces, wherein two first force transmission surfaces of each clamping jaw can respectively be brought into contact with the force receiving surfaces of the clamping and positioning bolts of the first clamping plate when the clamping and positioning bolts of the first clamping plate are engaged with the first set of clamping openings, and two second force transmission surfaces of each clamping jaw can respectively be brought into contact with the force receiving surfaces of the clamping and positioning bolts of the second clamping plate when the clamping and positioning bolts of the second clamping plate are engaged with the second set of clamping openings.