The seatbelt, recognized as the most effective restraint system for automotive occupants, exerts restraint forces on the shoulders and pelvis during crashes, thereby mitigating occupant injuries. Data from frontal crash accidents reveal that rib fractures constitute a significant proportion of chest injuries, closely associated with the seatbelt path. In vehicle crash safety tests, chest injuries are a primary source of scoring items. To optimize chest injury for rear female dummies in a 100% FRB test for a specific vehicle project, this study combines frontal sled tests with static seatbelt path tests for H3 female dummies. The analysis focused on the relationship between seatbelt paths and chest compression in dummies. Results indicate that an upward shift in the seatbelt path reduces chest compression in H3 female dummies. The probability density function of the seatbelt midpoint follows a Gumbel distribution, and the position of the upper fixed point of the seatbelt significantly influences the fitted seatbelt path distribution. Consequently, this study quantifies the distribution of seatbelt path under various upper fixed point positions, providing theoretical guidance for predicting chest injuries at the early stages of a vehicle safety project.