A scan driver includes a plurality of stages for respectively outputting a plurality of scan signals, an N-th stage of the stages including a shift register for outputting an N-th carry signal based on a frame start signal or based on a carry signal from a previous stage, and an output control block for outputting the N-th carry signal as an N-th scan signal in a display mode, and for repeatedly outputting active periods of the N-th scan signal during an active period of the N-th carry signal in a sensing mode, wherein N is a positive integer.