The current work studies the fracture mode partition in beam-like geometries as a function of cohesive properties. It is observed that the mode mixity exhibits a unique dependence on the cohesive zone length scale, where the lower and upper bounds are given by the local and global partitioning. Based on this observed unique dependency, a new semi-analytical cohesive analysis (SACA) is proposed for partitioning. This partitioning method is applied to previously conflicting experimental data in the literature, and physically consistent results are obtained in each case, suggesting that this novel SACA method can be used to obtain accurate mixed mode partitioning now always.