This paper presents an innovative approach for analyzing highly nonlinear oscillators. The main objective is to apply the generalized He's frequency formula (HFF) to study the analytical solutions of specific types of extremely nonlinear oscillators. The paper discusses the non-perturbative approach (NPA), which converts nonlinear ordinary differential equations (ODEs) into linear ones, allowing for the derivation of a new frequency comparable to that of a linear ODE. This method is straightforward, requires less processing, and provides results that are more accurate than other approximate methods. The NPA is validated through numerical analysis using Mathematica software, showing strong agreement with numerical solutions. Unlike traditional perturbation methods, the NPA does not rely on Taylor expansions and is capable of stability analysis. The paper highlights the NPA's versatility in addressing various nonlinear problems, making it a valuable tool in engineering and applied science. The HFF, developed by He, is a key component of the homotopy perturbation method and is known for its simplicity and efficiency in solving weakly nonlinear oscillators. The Duffing frequency, proposed by He, is a valuable mathematical tool for studying periodic solutions in nonlinear oscillators. The NPA, which circumvents the limitations of perturbation methods, is particularly effective in systems with strong nonlinearities. El-Dib's formulae are also discussed, which are designed to handle complex nonlinearities and provide precise frequency estimations. The NPA is shown to be effective in various complex systems, including high-energy physics and engineering applications where weak nonlinearity assumptions do not hold. The paper concludes that the NPA is a more reliable and versatile method for analyzing highly nonlinear oscillators.This paper presents an innovative approach for analyzing highly nonlinear oscillators. The main objective is to apply the generalized He's frequency formula (HFF) to study the analytical solutions of specific types of extremely nonlinear oscillators. The paper discusses the non-perturbative approach (NPA), which converts nonlinear ordinary differential equations (ODEs) into linear ones, allowing for the derivation of a new frequency comparable to that of a linear ODE. This method is straightforward, requires less processing, and provides results that are more accurate than other approximate methods. The NPA is validated through numerical analysis using Mathematica software, showing strong agreement with numerical solutions. Unlike traditional perturbation methods, the NPA does not rely on Taylor expansions and is capable of stability analysis. The paper highlights the NPA's versatility in addressing various nonlinear problems, making it a valuable tool in engineering and applied science. The HFF, developed by He, is a key component of the homotopy perturbation method and is known for its simplicity and efficiency in solving weakly nonlinear oscillators. The Duffing frequency, proposed by He, is a valuable mathematical tool for studying periodic solutions in nonlinear oscillators. The NPA, which circumvents the limitations of perturbation methods, is particularly effective in systems with strong nonlinearities. El-Dib's formulae are also discussed, which are designed to handle complex nonlinearities and provide precise frequency estimations. The NPA is shown to be effective in various complex systems, including high-energy physics and engineering applications where weak nonlinearity assumptions do not hold. The paper concludes that the NPA is a more reliable and versatile method for analyzing highly nonlinear oscillators.