A fixing device includes a rotator having a heat generation layer, an excitation coil to inductively heat the heat generation layer, ferromagnetic cores to direct magnetic flux arising from the excitation coil to the rotator, and a holder to hold the excitation coil and the ferromagnetic cores. In the fixing device, the ferromagnetic cores include multiple cores disposed astride the excitation coil at a turning part on each end of the excitation coil in a longitudinal direction of the excitation coil.