An image forming apparatus, includes an image processing device to perform processing, using electrical power supplied from a supply source, the supply source being selected from it commercial power supply, a first electrical power storage device, and a second electrical power storage device, the second electric power supply storage device supplying electric power in an amount smaller than an amount supplied from the first electric power supply storage device; and circuitry to control the processing to be performed by the image processing device according to the selected supply source. When the supply source is the first electrical power storage device, the circuitry controls the image processing device to execute processing that is executable when the supply source is the commercial power supply. When the supply source is the second electrical power storage device, the circuitry controls the image processing device to execute a part of the processing that is executable when the supply source is the commercial power supply.