In order to study the hydration kinetics of geopolymers more accurately and avoid errors caused by exothermic data during the induction period and inaccurate calculation of kinetic parameters due to multiple exothermic peaks, a method was proposed to calculate the reaction kinetics equation using geopolymer color change data. A fixed area of the geopolymer hydration process was continuously recorded using a digital microscope. Images were captured at 1-minute intervals, and a total of 9 999 images were acquired over a period of 6 days and 22 hours. The images were converted into color numerical matrices using MATLAB. The average pixel value (APV) of each image was calculated, and the final APV at t=∞ was obtained by means of curve fitting or extrapolation based on the Knudsen equation. The conversion rate (α) of the geopolymer reaction process was subsequently determined using the APV data. Finally, α was substituted into the differential and integral equations of the Krstulovic-Dabic reaction kinetics model. The results indicate that the calculation of color data enables the characterization of three fundamental processes during geopolymer hydration, namely nucleation and crystal growth (NG), phase boundary reaction (I), and diffusion (D). This approach yields key kinetic parameters, including the reaction rate constant (K) and the reaction order (n), as well as the relationships between the reaction rate and the degree of reaction at each stage. Furthermore, the derived reaction rate curves for individual stages provide a good fit to the actual hydration rate dα/dt curve of the geopolymer, based on its color characteristics.