To increase the detection sensitivity of a touch panel, increase the visibility of a touch panel, provide a bendable touch panel, provide a thin touch panel, or provide a lightweight touch panel. The touch sensor has a first substrate, a first conductive layer, a second conductive layer, and an insulating layer. The first conductive layer includes a region between the first substrate and the second conductive layer. The insulating layer includes a region between the first conductive layer and the second conductive layer. The first conductive layer, the second conductive layer, and the insulating layer form a capacitor. The second conductive layer has an opening. The opening in the second conductive layer and the first conductive layer overlap with each other in a region.