A fixing device includes a primary heater disposed opposite a fixing rotator to heat a circumferential span of the fixing rotator other than a fixing nip formed between the fixing rotator and a pressure rotator and a secondary heater disposed outboard from the primary heater in an axial direction of the fixing rotator to heat the fixing rotator at the fixing nip. The primary heater and the secondary heater heat a bi-heating span of the fixing rotator in the axial direction thereof. The secondary heater heats a mono-heating span of the fixing rotator in the axial direction thereof and generates a decreased amount of heat to be conducted to the bi-heating span of the fixing rotator. The decreased amount of heat is smaller than an increased amount of heat to be conducted to the mono-heating span of the fixing rotator that is heated by the secondary heater only.