IEC 63299:2022 specifies classification rules for metallic magnetic powder cores used in inductive components fulfilling the requirements of the electronics industries. This document addresses the following objectives for magnetic powder cores suppliers and users: - cross-reference between core materials from multiple suppliers; - assistance to users in understanding the published technical data in catalogues when comparing multiple suppliers; - guidance to users in selecting the most applicable core for each application; - establishing uniform benchmarks for suppliers for performance in the new development of core material.