A display device includes a scale factor provider, a grayscale converter, and pixels. The scale factor provider calculates an n-th scale factor based on n-th input grayscales received during an n-th frame period. The grayscale converter calculates (n+p)th output grayscales by applying the n-th scale factor to (n+p)th input grayscales received during an (n+p)th frame period in a first mode. The pixels output light to display an image based on the (n+p)th output grayscales, where n is an integer greater than 0 and p is an integer greater than 1.