The easiest one is to use the Multiplet Analysis tool. To calculate coupling constants in MestreNova, there are several options. How does MestreNova measure coupling constant? Mnova NMR processes your data (1H, 13C or any other 1D NMR as well as any 2D correlations, such as HSQC, HMBC, NOESY, COSY, TOCSY, etc.) MestreNova is spectral data analyzing software, which can be run on Windows, Mac OS and whole range of Linux distributions.