An image forming apparatus includes a document reading section and an image forming section. The document reading section reads a document image placed on a paper placement table and generates image data. The image forming section forms an image on a sheet of paper on the basis of the image data, and includes a memory that stores test data representing a test image, which is to be formed on a sheet of paper having a size larger than the size of the table, a correction-amount calculation unit that calculates correction amounts on the basis of image data representing the test image which is formed on the sheet of paper and which has been read by repeating an operation, and a correction-amount memory that stores the correction amounts. The image forming section forms, on a sheet of paper, an image corrected on the basis of the correction amounts.