This paper highlights the strength and durability characteristics of geopolymer concrete (GPC) developed with ground‐granulated blast furnace slag (GGBS) and metakaolin (MK) as binders. Sodium hydroxide (NaOH) and sodium silicate (Na2SiO3) were used as alkaline activators of GPC. The variable parameters considered in this research work were proportions of GGBS and MK. The optimum mix was obtained by varying the proportions in the binder content of GPC. The influence of recycled coarse aggregates (RCAs) was also assessed on the arrived optimum GPC mix and compared with natural coarse aggregates. The replacement of RCA was done at 25, 50, and 100%. The durability studies were performed on the arrived optimum mix for natural and RCA concrete. The durability properties of GPC were studied by exposing the concrete specimens to HCl and H2SO4 at 5% concentration for 7, 28, and 56 days. Acid mass loss factor and acid strength loss factor were determined at all ages. From the results, it is observed that the usage of supplementary cementitious material as a partial replacement of GGBS in GPC is improving the strength as well as durability properties of blended GPC. The comparisons of these parameters were examined for the usage of RCA proportions also. The results indicated that the inclusion of RCA up to certain proportions is showing satisfactory results compared to that of GPC with natural aggregates.