Gage Repeatability and Reproducibility (Gage R&R) is a vital tool in understanding the reliability of measurement systems, especially in high-precision environments where Coordinate Measuring Machines (CMMs) are used. This analysis quantifies the variation introduced by the CMM, the operators, and the measurement process itself. By examining both repeatability and reproducibility, manufacturers can determine if their CMM-based inspections are trustworthy enough to make critical quality decisions. This guide explains how to conduct a Gage R&R study, interpret the results, and apply key formulas to evaluate your system’s performance.