A display device includes a display panel including pixels, and a driver to drive the display panel based on input image data. The driver performs a sensing operation for the pixels, to selectively perform the sensing operation by comparing grayscale values of the input image data and a reference grayscale value, to selectively perform a luminance control operation for controlling luminance of the display panel in response to a luminance control signal, and to adjust the reference grayscale value when the luminance control operation is performed.