A display device comprises pixels, an emission control driver, a scan driver, and a timing controller for selecting whether the display device is to operate in a first display mode in which the display device is driven at a first frequency or a second display mode in which the display device is driven at a second frequency lower than the first frequency based on input image data. The first display mode comprises first frame periods, and the second display mode comprises second frame periods having at least two sub-frames having a period equal to the first frame period. A total time required to supply the scan signals to the scan lines in one first frame period of the first frame periods and a total time required to supply the scan signals to the scan lines in one second frame period of the second frame periods are substantially same.