Microcantilever is the fundamental structure for the realization of a microelectromechanical systems sensor with higher sensitivity and selectivity in a number of fields like biomedical, defense, and environmental. Present research is also focusing on the applications of microcantilever in the field of food industry. Among the two fundamental techniques for microcantilever, deflection and resonant peak shift, it was proven that the latter one is the best suited for added mass detection. In our study, we derive an analytical expression for δm based on the shift in frequency (δf') that accounts for the elasticity of the added mass and the location of the mass on the beam. In particular, we create a finite element methods model of our system in a commercial package, COMSOL (Bangalore, India), and carry out modal analysis for the cantilever beam resonator with and without the added mass, varying the relative stiffness and mass of the two components (the cantilever beam and the added mass), to compare the results of shift in resonant frequency with those obtained from rigid mass models. The results show the effect of elasticity clearly in certain ranges of relative stiffness and mass.