The embodiments relate to display devices and driving methods thereof. A display device includes a display panel including sub-pixels arranged thereon, a gate driver configured to applying a scan signal to the sub-pixels, and a controller configured to sense a characteristic value of the sub-pixels, wherein the controller outputs a first clock and a second clock based on a count value increasing sequentially from an initial value during a sensing period for sensing selected sub-pixels, the gate driver generates a gate clock signal in synchronization with the first clock and the second clock and the scan signal based on the gate clock signal.