Cement is the most used construction material, and producing 1 kg of cement involves the emission of 0.9 kg of carbon dioxide (CO2), which is approximately 8% of total carbon emission. Emission of CO2 makes up roughly 65% of the greenhouse gas that is the major cause of global warming. Alternative binders must be developed to mitigate the environmental consequences caused due to cement and to be used as construction materials. The production of an inorganic alumino-silicate polymer known as geopolymer, developed from byproducts like fly ash, rich in silicon- and aluminum, is one effort to produce eco-friendly construction material. Also, given the significant amount of FA produced by coal-fired power plants annually, there is a growing need to find ways to manage this waste product. Using it as a resource material in geopolymer production is a promising solution. Hence, the present study investigates the potential of geopolymer solutions having different molar concentrations (4–16 M) of potassium hydroxide (KOH), sodium hydroxide (NaOH), and the ratio of sodium silicate and sodium hydroxide (Na2SiO35H2O/NaOH). The geopolymer samples are prepared and cured under controlled temperature (40, 60, and 80 °C) and time (1 day). The results reveal that the geoplymerization using a NaOH concentration of 12 M has pronounced an optimum concentration in achieving the ultimate strength gain of FA compared to cement. This finding is significant because it provides useful information for developing fly ash-based geopolymer products. Further, experimental results are elucidated based on micro-level investigations such as XRD and SEM.