MnZn-based ferrite materials like the EPCOS N87 or K2004 are commonly used as magnetic cores in inductive power transfer (IPT) applications. However, the performance and reliability of the IPT systems are limited by ferrite's intrinsic brittleness and low flux density saturation point. In this paper, a study of nanocrystalline ribbon based magnetic cores for IPT applications is presented. FEM simulations and experimental validations are used to compare both materials. The design of ultra-thin laminated cores such as nanocrystalline ribbons for IPT systems is presented. Compared to ferrite, nanocrystalline ribbon is mechanically more robust and it has higher magnetic permeability and a higher saturation point. Results show that nanocrystalline ribbon cores achieve more than 50% volume reduction of the IPT pads due to its high saturation point. However, a compromise arises as the total power loss increases due to the induced eddy currents in the core. The reduction of efficiency can be mitigated by special geometrical design of the nanocrystalline ribbon core. A 6.6 kW IPT system has been built for experimental validation of the design methodology.