A touch sensor including a substrate including an active area and a non-active area, a plurality of first electrodes extending in first direction on the active area, a plurality of second electrodes extending in a second direction crossing the first direction on the active area, a plurality of third electrodes including electrode portions disposed in the first electrodes, respectively, being separated from the first electrodes, and extending in the first direction on the active area, and a sensing circuit including a plurality of signal receivers receiving sensing signals from the first electrodes, respectively, in which each of the signal receivers includes first and second input terminals connected to a pair of first and third electrodes corresponding to each other, respectively, and outputs a signal corresponding to a voltage difference between the first and second input terminals.