An image forming apparatus including at least one latent image carrier, an image forming unit to form a toner image on the at least one latent image carrier based on image data, a transfer body onto which the toner image formed on the at least one latent image carrier is transferred in one or more valid image ranges, a non-image range determiner to determine a non-image range on a surface of the transfer body onto which the toner image is not transferred, a surface detector to detect the surface of the transfer body in the non-image range, and a toner determiner to determine whether or not toner is present in the non-image range based on a result detected by the surface detector.