It is known that the calculation of soil parameters in different ways in geotechnical engineering is important in terms of interpretation and obtaining reliable results. The subgrade reaction coefficient can generally be calculated by field loading tests, laboratory tests and various empirical relations. The subgrade reaction coefficient obtained by using different methods and empirical relations can have very different values. The subgrade reaction coefficient calculations, which are one of the most important parameters used in the interaction of the soil and structure, are mostly not used correctly and the large differences between the results obtained with various approaches affect the determination of the subgrade reaction coefficient in a realistic manner. Subgrade reaction coefficient depends on soil settlement and elastic modulus and therefore on parameters such as Poisson ratio, soil type, unit volume weight values, seismic velocities, safe bearing capacity value. In this study, the previous correlations of various researchers in determining the subgrade reaction coefficient were examined. In the light of these studies, the subgrade reaction coefficient values calculated from the data obtained from three different locations in Batman city were compared and their compatibility was questioned. It was determined that the subgrade reaction coefficient values obtained from the Standard Penetration Test (SPT) impacts provided higher and different results than the others, and the subgrade reaction coefficient values calculated according to the S wave speed obtained from the safe bearing capacity value, geophysical measurements and soil settlement provided closer results. S wave velocity obtained from seismic methods provides information about the resistance, strength and rigidity of the units on the soil. Therefore, the formulas calculated using S wave velocity is important. Standard Penetration Test (SPT) can yield misleading results when standard and qualified equipment is not used and when it is applied by personnel with insufficient experience. The same impact and power may not be applied to the soil every time during the application phase. This results in misleading and unreliable blow counts. Therefore, calculating the subgrade reaction coefficient, especially in structures with a settlement problem, by considering all of these parameters will give more reliable results.