Hydrogen is a high energy content fuel and methane is currently the most preferred feedstock for hydrogen production. Direct thermal splitting of methane offers the cleanest technique to produce hydrogen and carbon as coproduct fuel. Carbonaceous catalysts have significant impact on methane to hydrogen conversion. This study presents thermogravimetric experiment results of carbon-catalyzed methane decomposition using commercial catalyst. Results are presented in terms of carbon formation rate, amount of carbon deposition on the catalyst, sustainability factor, catalyst activity, and kinetics of the reaction. The results show that weight gain because of carbon formation depends on reaction temperature, methane volume percent in the feed gas, and nature of the carbonaceous catalyst. It was observed that the reaction rate was dominant at the beginning, and deactivation rate was dominant toward the end of reaction. X-ray diffraction (XRD) and scanning electron microscopic (SEM) analysis of deactivated catalytic samples show decreasing disorder with increasing reaction temperature. Finally, performance comparison of activated carbons (ACs) studied in literature shows that activated carbon sample chosen in this study outperforms in terms of carbon deposition, reaction rate, carbon weight gain, and sustainability factor.