The horizontal-to-vertical spectral ratio method is one of the most commonly utilized techniques to estimate the site response. This method is frequently preferred for practical calculation of the dynamic properties of soil layers. Recently, the popularity of this technique has been increasing thanks to the methods developed to obtain the shear wave velocity profile from the horizontal-to-vertical spectral ratio. In this study, a MATLAB-based graphical user interface has been developed for inversion and forward calculation of the horizontal-to-vertical spectral ratio. This code uses the equivalent linear approach based on the viscoelastic Kelvin-Voigt model to compute the theoretical site response of the horizontally stratified soil layers. Furthermore, the developed graphical user interface can easily estimate the dynamic parameters such as thickness, shear wave velocity, density and damping ratio of the soil layers through an elitist genetic algorithm, and thereby obtain the shear wave velocity profiles. The reliability of the developed algorithm has been tested using the synthetic and real datasets. The results from the real data examples have been compared with those from previous studies and the satisfactory results have been obtained.