An image processing device changes a size of original image represented by an original image data to create size-changed image data representing a size-changed image and outputs the size-changed image data to an output device. The image processing device has an image size determination unit determines a target image size based on a ratio of a predetermined standard character size to a character size regarding character data included in the original image data and based on an image size of the original image data. An image data creating unit changes the size of the original image to create the size-changed image data based on the determined target size. An output control unit controls an output of the created size-changed image data to the output device such that the size-changed image is shown within the image formation area in the output image.