In this paper, three numerical methods are employed to solve the nonlinear Duffing equation: a hybrid block method, the Homotopy Perturbation Method (HPM), and the Multistep Differential Transform Method (Ms-DTM). The proposed hybrid block method is based on an approximate power series solution, where collocation is applied at three points and interpolation at two points to generate a system of five equations. This structure enhances both accuracy and computational efficiency. All three methods are implemented and compared through a numerical example to determine their performance. The results demonstrate that the hybrid block method provides improved accuracy and stability, making it a competitive approach for solving nonlinear differential equations.