A system and method for calibrating a melt pool monitoring system of an additive manufacturing machine includes installing a calibration system on the machine and performing a calibration process. Specifically, the calibration system includes a calibration platform removably mountable to a build platform of the additive manufacturing machine and having calibrated electromagnetic energy sources mounted thereon for defining a measurement standard. The electromagnetic energy generated is measured by the melt pool monitoring system and compared to the known measurement standard to determine whether system adjustments would improve process tolerances or uniformity.