The predominant imaging techniques used for preclinical research currently include optical imaging, magnetic resonance imaging (MRI), and nuclear medicine [1]. While these techniques have widespread pre-clinical adoption, they face challenges such as signal attenuation with tissue depth, lack of quantitativeness, radiation dose, and poor image contrast. By imaging the nonlinear magnetism of iron oxide nanoparticles, magnetic particle imaging (MPI) can overcome these challenges for quantitative, high-contrast imaging anywhere in the body while using no ionizing radiation [2-3]. There have not been head-to-head comparisons of MPI to the existing pre-clinical imaging modalities. In this abstract, we demonstrate quantitative performance comparisons in vivo and ex vivo between MPI, CT, Optical, and MRI imaging techniques.