2D Magnetic Resonance Elastography (MRE) is a validated method for staging liver fibrosis via liver stiffness measurements produced by introducing and imaging acoustic waves. Newer 3D MRE additionally images waves propagating out-of-plane. This retrospective study compared 2D and 3D liver MRE stiffness measurements across 600 patient exams. The two methods had excellent agreement, with 3D MRE yielding 6% lower stiffness and having lower failure rate. 3D MRE, which has the same acquisition time, is a good alternative for liver imaging as it does not suffer from out-of-plane propagation bias and has the added potential to characterize smaller abdominal organs.