Lattice structures are essential in lightweight and high-performance applications, leveraging additive manufacturing to achieve optimized mechanical properties. However, tensile testing of these structures remains challenging due to their complex geometries, anisotropic behavior, and gripping difficulties, which can lead to stress concentrations and premature failure. This work developes a systematic framework for designing and standardizing tensile lattice specimens by employing a finite element reduced-order model based on compensated beam modeling. This approach significantly reduces computational costs while accurately capturing the mechanical response of intricate lattice topologies. Additionally, an innovative merit index based on the average strain energy density is introduced to minimize mesh dependency in simulations. Using this methodology, key tensile specimen parameters—such as unit cell dimensions, porosity, and gripping mechanisms—are optimized. A transition zone is incorporated to ensure smooth stress distribution, reducing stress concentrations and enhancing structural reliability. The proposed framework provides a solid foundation for future research and industrial applications, enabling accurate and efficient tensile characterization of lattice structures.