Silver nanowires (AgNWs) and gold nanowires (AuNWs) have high surface area, high electrical conductivity and excellent chemical stability, and hence are attractive building blocks to fabricate low-density metal foams for a wide range of applications. Here we demonstrated using solution synthesis to produce high-purity AgNWs and AuNWs in large quantities, which are subsequently used to fabricate (ultra)low-density forms via freeze-casting approach. As-made metal foams have tunable densities down to single-digit mg/cc. Key factors that affect the pore geometries, including solvent, freezing rate and nanowire concentrations, were systematically investigated. This work was performed under the auspices of the U.S. DOE by LLNL under Contract DE-AC52-07NA27344.