Fracture toughness (KIC) is a property which describes the ability of a material to resist fracture. Complexity exists in the determination of KIC due to its dependency on microstructure. It is beneficial to develop computer-based physical models that can calculate the microstructure-dependent KIC to reduce the experimental cost. This study explores the feasibility of Hahn-Rosenfield model in the evaluation of KIC of a wide range of Titanium and Aluminium alloys at room temperature. The model is correlated to the microstructure information calculated in JMatPro®, such as the fraction of alpha-beta in Titanium and detrimental precipitate phases in Aluminium. The majority of the calculated results fall within 30% limit region from the measured value. The methodology can ultimately aid the materials processing and structural integrity assessment.