A display device includes a pixel unit including first and second pixel columns arranged alternately along a first direction, and a third pixel column arranged between the first and the second pixel columns, a timing controller generating first or second image data by converting input image data, and a data driver generating a data voltage corresponding to the first or second image data and supplying the data voltage to the pixel unit. The first and second pixel columns each include first and second color pixels arranged alternately along a second direction, the third pixel column includes a third color pixel arranged along the second direction, and the timing controller compares a difference value between a grayscale value of the first color pixel and a grayscale value of the second color pixel with a reference value, and generates the second image data based on a comparing result.