Abstract: The study used the two-parameter Weibull distribution function to analyze data obtained from electrochemical potential monitoring experiments. Two sets of fifteen steel-rebar test samples admixed with varying concentration of aniline, potassium dichromate and their synergistic combination with fixed amount of sodium chloride salt partially immersed in NaCl and H₂SO₄ solution at ambient temperature had their potential readings taken in accordance with ASTM C 876. Performance quality and consistency of the inhibitor was then estimated by the Weibull probability density distribution as an extreme value statistical modeling approach to study the efficacy and predict the most efficient inhibitor concentration in each media. The study also investigated the effect of the inhibitors on the compressive strengths of the reinforced concrete samples. Test sample admixed with 0.34 and 0.41 M aniline was predicted as exhibiting the best inhibiting quality in NaCl medium while in the H₂SO₄ medium the synergistic combination of 0.03 M K₂Cr₂O₇ and 0.30 M aniline exhibited the best performance. The compressive strength values of test sample admixed with 0.41 M aniline was the highest in both the microbial (303 KN) and marine (315 KN) medium while the control test sample in the NaCl medium showed the highest overall increase (330 KN) in compressive strength.