One of the most widely used lipid force fields, CHARMM36, was originally parametrized and validated on SAXS measurements of lowhydrated DOPC multilamellar phase and was later modified to reproduce better deuterium order parameters of fully hydrated bilayers of six different phospholipids. Another popular force field, OPLS, with its origins in OPLS-AA and now under development as a proprietary force field by Shrödinger Inc., was parametrized to reproduce solvation of a broad range of small molecules. As details of the OPLS4 lipid parametrization or benchmarks of its performance have not been provided by Schrödinger, we wish to validate it here. To our knowledge, neither force field has been intensively vali-dated for reproducing lipid dehydration, but both are expected to be strong candidates for capturing the molecular details of this crucial biomembrane process.