A touch sensor includes sensing blocks. Each of the sensing blocks includes first sensing cells of a first group, first sensing cells of a second group, and second sensing cells. The first sensing cells of the first group are arranged in a first direction, spaced apart from each other with first separation areas therebetween, and coupled to an identical first electrical node. The first sensing cells of the second group are arranged in the first direction, spaced apart from each other with second separation areas therebetween, and coupled to an identical second electrical node. The second sensing cells respectively extend in a second direction in the first separation areas and the second separation areas. First sensing cells at borders of respective sensing blocks adjacent in the first direction are coupled to different electrical nodes.