<p>This study presents a novel model for evaluating non-equi-biaxial surface residual stresses in metals using surface in-plane displacements around an indentation, as an alternative to the commonly used instrumented force-depth curve. The surface X- and Y-displacements are measured within an annular region around the indentation imprint by Digital Image Correlation with random patterns generated from surface scratches. Integration of these displacements allows for evaluating principal residual stress magnitudes and directions by comparing the results from stressed and stress-free specimens. The effects of stress state and material property were investigated within a series of finite element simulations, and an alternative way was developed to eliminate the need for stress-free specimens. Experimental validation was conducted on specimens with known non-equi-biaxial stress states.</p> Graphical Abstract <p></p>