An image forming apparatus includes an image forming section that forms an image, a plurality of detectors that detect an amount of variation of indicators respectively determining an amount consumed of the consumable supply, a determination section that determines whether or not the amount of variation has reached any one of first lifespan values, an interruption section that interrupts an image forming operation based on the first lifespan values, and an extension setting section that inhibits the interruption of the image forming operation and sets an extension mode of extending a period of execution of the image forming operation, wherein the determination section determines whether or not an amount of variation of one indicator has reached an extended lifespan value when the extension mode is set, and wherein the interruption section interrupts the image forming operation based on extended lifespan value when the extension mode is set.