Induction heated fixing device and image forming apparatus

A fixing device includes a fixing member that fixes toner on a recording material; a magnetic-field-producing unit including an exciting member that produces an alternating-current magnetic field, and first magnetic-circuit-producing members that each produce a magnetic circuit of the alternating-current magnetic field and are provided at a predetermined first interval and a second interval, smaller than the first interval, in a longitudinal direction of the fixing member; a temperature measuring device that measures the temperature of the fixing member; and a second magnetic-circuit-producing member having a cut portion in which the temperature measuring device is provided and that produces a magnetic circuit of the alternating-current magnetic field while conducting heat to the fixing member by being induction-heated.