An image forming apparatus includes a storage unit configured to store correction data; an identifying unit configured to identify a correction amount for a correction target pixel based on the correction data stored in the storage unit; a correction unit configured to correct an exposure amount of the correction target pixel among a plurality of pixels indicated by image data, from an exposure amount indicated by the image data, based on the correction amount for the correction target pixel; and an image forming unit configured to form an image based on an exposure amount after correction by the correction unit. The correction data includes only a correction amount corresponding to each of representative parameter values of a plurality of parameter values of a parameter for varying the correction amount.