Benchmark measurement data should be produced under controlled conditions with processing parameters that are tied to physically accurate units with well-quantified measurement uncertainties. In this presentation, approaches for a characterizing the Fundamentals of Laser-Matter Interaction (FLaMI) laser-based metal additive manufacturing (AM-LB/M) testbed at the National Institute of Standards and Technology (NIST) will be discussed. Specifically, methods will be described for calibrating laser power, power density distribution, scan speed, turnaround time, positioning accuracy, and more. These machine performance measurands directly correspond to the conditions under which the Additive Manufacturing Benchmark Series (AM-Bench) Challenge Problems AMB2025-06 and AMB2025-07 were executed [1]. Additionally, benchmark measurement data should be produced with well-characterized metrology. Specifically, the calibrations and characterizations of the thermographic camera and optics used to measure the pad cooling rate and time above melting for the aforementioned AM-Bench challenge problems will be detailed. Finally, the results of some of NIST’s most unique optical metrology capabilities that pertain to AM-LB/M will be previewed. REFERENCES [1] National Institute of Standards and Technology. AMB2025-06 and AMB2025-07 Benchmark Measurements and Challenge Problems (2025). https://www.nist.gov/system/files/documents/ 2025/03/20/AMB2024-06%20and%2007%20challenge%20descriptions_v3.pdf