A gauge, which is used in examining the accuracy of a coordinate measuring machine (CMM), enables total calibration of errors and numbers of revisions of the measured values. The accurate calibration is possible for a CMM of any size. Various machines can also be calibrated by combining the gauge.The CMM calibrating gauge consists of a block gauge and a fixed sphere. The coordinates of the sphere’s center and diameter can be specifically measured on the basis of the opposite end faces of the block gauge. Furthermore, the CMM calibrating gauge may have numbers of block gauges that are fixed together, allowing measured values to be revised repeatedly.