A display device is disclosed. In one embodiment, the display device includes a first conversion unit receiving gray data and outputting a gray data value of a second gamma curve, which has a luminance equal to a luminance of the gray data on a first gamma curve. The device may also include a memory storing a look-up table (LUT) which includes first and second data groups and compensated gray data for the second gamma curve. The device may further include a reference unit generating the compensated gray data based on the two converted gray data. Coordinates formed of i) each value in the first data group and ii) each value in the second data group may correspond to any one of the compensated gray data.