High frequency magnetic cores are commonly used in inductors and transformers for power electronic converters. However, the state-of-the-art ferrite materials for magnetic cores have low magnetic saturation and the powder materials have low permeabilities. Those cores also require high temperature or high pressure to form thus their geometries and permeabilities cannot be adjusted by the end user. We propose the Fe-Cu-Nb-Si-B based nanocrystalline soft-magnetic ribbons as the building element to achieve customised permeability and geometry for cores in different inductive components. The FeCuNbSiB based nanocrystalline alloy is compounded with polymer films or thin insulators to form anisotropic magnetic ribbon. Such flexible ribbons can be stacked or wound to different shapes with different permeabilities. The magnetic core for high power inductive power transfer applications using soft-magnetic ribbons will be used to show the potential of such technologies.