Metal‐free carbon electrodes with well‐defined composition and smooth topography are prepared via sputter deposition followed by thermal treatment with inert and reactive gases. X‐ray photoelectron spectroscopy (XPS) and Raman spectroscopy show that three carbons of similar N/C content that differ in N‐site composition are thus prepared: an electrode consisting of almost exclusively graphitic‐N (NG), an electrode with predominantly pyridinic‐N (NP), and one with ≈1:1 NG:NP composition. These materials are used as model systems to investigate the activity of N‐doped carbons in the oxygen reduction reaction (ORR) using voltammetry. Results show that selectivity toward 4e‐reduction of O2 is strongly influenced by the NG/NP site composition, with the material possessing nearly uniform NG/NP composition being the only one yielding a 4e‐reduction. Computational studies on model graphene clusters are carried out to elucidate the effect of N‐site homogeneity on the reaction pathway. Calculations show that for pure NG‐doping or NP‐doping of model graphene clusters, adsorption of hydroperoxide and hydroperoxyl radical intermediates, respectively, is weak, thus favoring desorption prior to complete 4e‐reduction to hydroxide. Clusters with mixed NG/NP sites display synergistic effects, suggesting that co‐presence of these sites improves activity and selectivity by achieving high theoretical reduction potentials while facilitating retention of intermediates. Co‐presence of pyridinic and graphitic N‐sites in metal‐free carbon electrodes modulates the binding energy of hydroperoxide/hydroperoxyl intermediates and promotes selectivity toward 4e‐reduction in the oxygen reduction reaction.