This study investigates the effectiveness of Digital Image Correlation (DIC) in measuring crack patterns and assessing their impact on collapse performance of earthquake-damaged precast concrete (PC) joints. Traditional methods for crack measurement, such as visual inspection and displacement gauges, often fall short in accuracy and scope, particularly under dynamic loading conditions. DIC, a non-invasive optical technique that analyses high-resolution images before and after deformation, offers a more precise approach. In this regard, the study applies DIC to PC beam-column joints, specifically two representative specimens, i.e., SED-P-I-H and MED-P-I-H, which were previously studied by Nguyen and Tan (2024b), subjected to seismic loading and followed by progressive collapse testing. The analysis of residual cracks from seismic loading stage and their effects on collapse behaviour highlight DIC’s capability for early detection and accurate measurement of crack characteristics, providing valuable data on deformation processes and enhancing structural mechanical models. The findings reveal significant variability in residual stiffness, load-carrying capacity, and deformation capacity compared to the JBDPA (2001) guideline, underscoring the importance of precise crack assessment for predicting structural integrity and guiding repair strategies. Given the high cost and precision of alternative equipment, the implementation of DIC in experiments is recommended for future studies on monitoring crack and deformation throughout loading.