We report the magnitude of the induced magnetic moment in CVD-grown epitaxial and rotateddomain graphene as a result of the proximity effect in the vicinity of the ferromagnetic substrates Co and Ni, using polarised neutron reflectivity (PNR). Although rotated-domain graphene is known to interact weakly with the ferromagnetic underlayer in comparison with the epitaxial graphene, the PNR results indicate an induced magnetic moment of ∼ 0.57 µ B /C atom at 10 K for both structures. The origin of the induced magnetic moment is found to be due to the opening of the graphene's Dirac cone as a result of the strong C p z -3d hybridisation, which was confirmed by additional PNR measurements using a non-magnetic Ni 9 Mo 1 and Cu substrates. We validated our PNR fitting models using the Bayesian uncertainty analysis and corroborated the results by X-ray magnetic circular dichroism measurements.