This study presents ChemEqT, a computational tool for calculating chemical equilibrium compositions and adiabatic flame temperatures in multicomponent fuel-air mixtures. The unified framework integrates Gibbs free energy minimization and the element potential method, enabling users to select the numerical strategy most appropriate for their application. The objective is to simplify the complexity of equilibrium combustion analysis while ensuring accuracy and computational efficiency. The performance of ChemEqT is validated through three representative case studies. In the first case, simulations of a propane-air mixtures involving 10 species yielded adiabatic flame temperature predictions with a maximum deviation of 0.32% and molar species deviations below 0.77% for CO2. The second case examines methane-air mixtures enriched with hydrogen, using 52 species, where the maximum deviation was under 0.04%. The third case involves adiabtic flame temperature predictions for 10 different fuel-air mixtures, with deviations below 0.146% for C3H6-air. These results confirm ChemEqT as a reliable and efficient tool for equilibrium-based combustion analysis, with strong potential for integration into broader energy system simulations. The accuracy and modularity of ChemEqT distinguish it from conventional solvers and make it a valuable asset for researchers working in the fields of combustion and energy systems.