An image forming apparatus includes a reading unit, a receiving unit, an image forming unit, a fixing unit, and a control unit. The reading unit generates generated image data indicating the image. The receiving unit receives external image data. The image forming unit forms, by using a recording agent, an image on a sheet based on the generated or external image data. The fixing unit fixes the recording agent on the sheet. The control unit controls to start raising a temperature of the fixing unit at a first timing, where a copy process is executed. The control unit controls to start raising the temperature of the fixing unit at a second timing, which is later than the first timing, where a printing process is executed.