We present a high precision lumped parameter model for efficient prediction of the resonant frequencies and coupling of cantilevered piezoelectric energy harvesters in absence of tip mass. Correction factors for the existing lumped parameter model are derived by comparing with the highly accurate distributed parameter model of cantilevered harvesters. First, a correction factor is defined for uncoupled lumped parameter model to predict the natural frequencies. Finally, the coupled lumped parameter model is subjected to a unified correction factor to accurately predict both the resonant frequencies and electrical outputs. The unified correction factor is derived by unifying the frequency and amplitude correction factors. The calculated outputs are in good agreement with the experimental results available in the literature. © 2001-2012 IEEE.