For six representative Fe and Ru complexes, we quantify differences in C-H hydroxylation kinetics by characterizing the full reaction coordinate (i.e., both transition states and reaction intermediates) with thermodynamic corrections for radical rebound propane hydroxylation. These six complexes, A-F, span nearly the full range of Ru DEI-L(resting) values with three of them comprising macrocyclic ligands (A, D, and F) and the remaining three comprising monodentate ligands (B, C, and E) (Supporting Information Figure ). Complexes B, C, and E all comprise ammonia ligands on the equatorial plane with water, hydrogen sulfide, and fluoride axial ligands, respectively. The equatorial ligands of A, D, and F comprise macrocycles formed from two units each of two distinct fragments, with A containing dimethylphosphine and furan fragments, D containing thiopyran and dimethylthioether fragments, and F containing dimethylamine and dimethylether fragments. The axial ligands for complexes A, D, and F are phenylphosphanide, phenol, and anilide, respectively (Supporting Information Figure ). We compute the full free energy landscapes in both the LS and IS states on the Fe and Ru analogues of these six complexes (Figure and Supporting Information Figures ). For kinetic analysis, we employ 2,6dichloropyridine 1-oxide as the oxidant, which was used in previous experimental studies. In addition to its experimental relevance, we chose this oxidant because it is more rigid during Oatom donation compared to N2O, which we have previously employed in computational studies, allowing for more straightforward convergence of transition states.