An image forming apparatus includes an image forming unit that forms an image using an electrophotographic process; a color measuring unit that measures a color of the image; a measured-value acquiring unit that acquires a measured value that is measured by the color measuring unit; and a set-value deciding unit that decides a set value related to formation of the image based on a difference between the measured value and a preset target value, wherein the set-value deciding unit determines the set value so that the image approaches a reference value in a period from a current state of the image to desired state of the image while optimizing a constraint evaluation function related to a constraint condition for the formation of the image by using an estimation equation for approximating time-series variation in a state of the image.