In range analysis (RA), suitable integer bit-widths are assigned to the variables so that no overflow occurs. Although the accuracy in RA rather than error analysis has more impact on hardware cost and efficiency, there are few works that offer new approaches to improve RA. Arithmetic functions, mostly represented by polynomials, are normally suitable for both optimization and verification purposes. In this paper, a safe and more accurate RA of feed-forward fixed-point polynomial data-flow graphs is proposed. The method employs particular features of RA and maps it to a specific class of polynomial optimization problems. The proposed method provides tighter ranges while taking less runtime in comparison with satisfiability-modulo theory-based method. Furthermore, the improved ranges lead to enhance the area and delay efficiency more than 50% and 24%, respectively, when the circuits are implementing the functions in comparison with the state-of-the-art techniques.