MeltWin® is an interactive analysis and visualization tool that provides a simple interface for extracting thermodynamic parameters for nucleic acid duplex formation from UV-detected melting curves. It provides algorithms for analyzing nucleic acid transitions using standard 2-state models, Ising models, and Tm/Concentrations dependence. Included are proprietary fitting and smoothing algorithms which enable accurate parameter calculations even for noisy data. In combination with wizards, data can be analyzed and results gathered quickly without knowledge of the underlying theory required.