An image forming apparatus comprises a detection unit that detects that a recording material is conveyed to a predetermined position on a conveyance path; a forming unit that forms an examination pattern at a defined position of the recording material; a reading unit that reads an image on the conveyance path when the recording material is being conveyed; a memory that saves read image data during a predetermined period defined based on a detection timing of the detection unit; a specifying unit that specifies an edge of the recording material by detecting an area corresponding to the conveyance path in the image data saved in the memory, and specifies an examination pattern area corresponding to the examination pattern based on the specified edge and the defined position; and an examining unit that examines the examination pattern area.