The energy eigenvalues with the Extended Cornell potential were obtained by analytically solving the radial Schrödinger equation using the Exact Quantization Rule technique (ECP). It was then used for computing the mass spectra of the heavy mesons like charmonium (cc-) and bottomonium (bb-) as well as heavy-light mesons such as bottom-charm bc- and charm-Strange cs- for various quantum states. Two exceptional cases such as the Coulomb and Cornell potentials, were taken into consideration when some of the potential parameters were set to zero. The current potential offers good outcomes when compared to experimental data and work of other researchers with a maximum error of 0.0065 GeV.