Large-area porous carbon is easily produced for supercapacitors from polyvinylidene chloride (PVDC) and polyvinylidene fluoride (PVDF) precursors, composed of carbon backbone and attached heteroatoms. The released heteroatoms during pyrolysis leave the porous carbon. This study explored the activation of both precursors using chemical agents (ZnO, Mg(OH)2, and KOH) to develop carbon with multiple micropores and mesopores. The activation process and relevant precursors were studied to implement synthesized porous carbon as an electrode in supercapacitors. During the activation of PVDC-resin, ZnO served both as templates and activating agents, while Mg(OH)2 served only as a template, and KOH served as an activating agent. For activation of PVDF, ZnO acted as a template and activating agent, whereas Mg(OH)2 and KOH impeded activation owing to side reactions. Therefore, with the above chemical agents, PVDC-resin was converted to carbon with a higher surface area than PVDF. The porous carbon produced using PVDC-resin with KOH had the highest specific capacitance of 137 F g− 1 and rate performance of 79% at 50 mV s− 1 (vs. 5 mV s− 1) owing to the successful creation of micropores and mesopores. This study identifies optimal conditions for synthesizing porous carbon using polymer precursors and chemical agents for supercapacitors.