Within each window, the biased probability density can then be reweighted , and a global free energy profile is then obtained by employing either the weighted histogram analysis (WHAM) the multiple Bennett Acceptance Ratio (mBAR) , or Umbrella Integration (UI) . US is routinely used to compute free energy surfaces associated with activated processes and its most common application in nucleation studies is the calculation of the free energy barrier to nucleation, i.e. Δ𝐹 * , without resorting to a theoretical formulation of the barrier dependence on thermodynamic parameters such as the solubility and surface tension . For the calculation of nucleation rates US calculations are complemented by estimates of the nucleation rate prefactor. This can be obtained by using CNT-inspired expressions following an approach similar to seeding simulations or, more generally, by drawing from the Bennett-Chandler formulation of the kinetic prefactor associated with a rare-event transition .