SpecTactix provides a powerful yet user-friendly solution for Fourier Transform Spectrometer resolution analysis, combining physics-based accuracy with modern app design. Unlike general-purpose scientific calculators, it focuses exclusively on FTS performance, delivering instant insights into spectral resolution, fidelity, and resolution-dependent path length requirements. With its clean interface, gradient visuals, and error-proof validation, SpecTactix empowers researchers and engineers to optimize experiments and evaluate system performance directly.