All structures with a crack are prone to failure, depending on the failure mechanism of the resonance-induced vibration. Periodic forces acting on a structure are combined with that structure's natural frequency to form the resonance. As a result, the natural frequency should be determined toestimate the periodic load resonance condition.In this study, a mild steel cantilever beam with a length of 3 m, a width of 0.25 m, and a depth of 0.20 m is considered. Modal analysis was used to study the natural frequency, mode shapes, and deflection of the first three modes of transverse vibration for a cracked cantilever beam. The cantilever beam's modal analysis is performed with a crack located from a fixed end at 0.5 m, 1 m, 1.5 m, 2 m, 2.5 m from the top, middle, and bottom faces of the cantilever beam. For all models, the crack's width and depth are fixed to 0.002 m and 0.1 m, respectively. For better outcomes, hexahedral meshing is utilized for cracked beams. The FEA simulation is carried out with the help of the ANSYS software. The theoretically obtained results are validated with the finite element analysis results to ensure the accuracy and the obtained results are approximately the same. The natural frequency of cracked beams decreases for the top and bottom surfaces, but the crack at the middle surface of the beam remains constant. Also, the effect of a crack is not uniform across all modes of vibration. As a result, the failure of a cracked beam can be identified, and corrective steps can be taken prior to the occurrence of cantilever beam fractures.