Rephasoniq is a cutting-edge scientific calculator that models the ultrafast behavior of reconfigurable metasurfaces by linking electrical bias and carrier mobility to optical phase-switch performance. It provides accurate estimates of switching latency and phase contrast through an elegant, physics-informed algorithm presented in a refined gradient interface. Designed for researchers, photonic engineers, and material scientists, Rephasoniq combines clarity, precision, and style—offering instant validation, interactive results, and seamless sharing in one intuitive platform that transforms complex metasurface analysis into a smooth, mobile experience.