InfraRed-Nucleation by Immersed Particles Instrument (IR-NIPI) is a cold plate immersion freezing instrument which measures freezing events using IR thermometery. Briefly, droplets of 50 uL volume are pippetted into multiwell plates which are placed on top of a stirling-engine based chiller which cools the droplets until they freeze. the temperature and the point at which droplets nucleate ice is recorded via an IR camera and custom python code.