A display device is disclosed. In one aspect, the display device includes a display panel including a display area and a non-display area surrounding the display area. The display device also includes a plurality of active pixels formed in the display area extending in first and second directions as a matrix, a plurality of dummy pixels formed in the non-display area and extending in the second direction, a repair test line and one or more active pixel test lines formed in the non-display area and extending in the first direction, a plurality of scan lines electrically connected to the active pixels and the dummy pixels and extending in the first direction, a plurality of data lines electrically connected to the active pixels and extending in the second direction, and at least one dummy data line electrically connected to the dummy pixels and extending in the second direction.