A scan driver includes stages for outputting scan signals. An nth stage includes: a first driving controller for controlling a voltage of a first node and a voltage of a second node in response to a previous carry signal; a second driving controller for controlling a voltage of a first driving node, based on a sensing-on signal, a next carry signal, the voltage of a first power source, the voltage of the first node, and a voltage of a sampling node, and controlling a voltage of a second driving node, based on the voltage of the sampling node and a sensing clock signal; an output buffer for outputting a carry signal and the scan signal; and a connection controller for electrically coupling the first node and the first driving node and electrically coupling the second node and the second driving node, in response to a display-on signal.