In this study, we developed a general mathematical relationship to determine hydraulic tortuosity. An optimization code was run in MATLAB R2014a software, using Monte Carlo algorithm, to determine tortuosity at different water contents for 69 soil samples of UNSODA. Considering fractal concepts, a linear equation was developed empirically to determine hydraulic tortuosity as a function of effective saturation, pore fractal dimension, porosity, inverse of air entry pressure, and soil water content. Based on the results, estimated values of tortuosity using the proposed relationship were greater than the values proposed by Shepard by about 30%. To evaluate developed equation, statistical parameters of Root Mean Square of Logarithmic Deviation (RMSLD) and Akaike’s Information Criterion (AICc) were used for 17 soil samples. According to the calculated statistical parameters, the developed equation to estimate tortuosity has improved the results of Shepard’s method. Though the developed equation has a relatively complicated structure, it displays acceptable performance in terms of the compromise between accuracy and complexity. Furthermore, based on calculated tortuosity values using developed equation, we determined pore continuity according to Burdine’s model (1953). Considering the results, calculated pore continuity is much less than the value proposed by Burdine (1953) and is approximately close to the values proposed by Mualem (1976).