Intrinsically disordered proteins (IDPs) adopt ensembles of rapidly fluctuating heterogeneous conformations, influencing their binding capabilities and supramolecular transitions. The primary conformational descriptors for understanding IDP ensembles-the radius of gyration (R(G)), measured by small-angle X-ray scattering (SAXS), and the root mean square (rms) end-to-end distance (R(E)), probed by fluorescent resonance energy transfer (FRET)-are often reported to produce inconsistent …