We assess the theoretical models of ionic microgel swelling, for both elastic formulations, by contrasting them against coarse-grained implicit-solvent simulations. In this regard, the parameters have been chosen such that the most relevant conditions are explored and analyzed. For that, the following parameters have been examined. For microgel topology, we have taken two cases: 1-N ch = 148 and N cross = 99; and N ch = 136 and N cross = 87. We have also considered microgel concentrations such that the monomer concentration varies in the range c mon = 1e-5 -0.03 σ -3 ; ionization degrees in the range Z/Z max = 0 -1; system salt concentrations in the range c sys = 0 -10 mM; and χ = 0.1. We numerically solve the nonlinear PB equation using the MATLAB routine bvp4c. A. Swelling modelling in the salt-free limit