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In this letter, the authors demonstrate isotropic Fe–Pt exchange-spring nanocomposite permanent magnets with a soft magnetic phase fraction of greater than 0.5 with a coercivity of 6.5 kOe, single-phase-like magnetic behavior, and an energy product of 25.1 MG Oe. Sub-10-nm Fe–Pt clusters are formed with compositions in the two-phase Fe3Pt and FePt regions. Intracluster structuring on a scale of a few nanometers occurs after appropriate heat treatment. This ensures full exchange coupling between the two phases, allowing greater soft magnetic phase fractions. The results provide insight into developing high energy product nanostructured permanent magnets.