According to one embodiment, a magnetic sensor includes a first element, a first wire, and a first magnetic part. The first element includes a first magnetic layer, a first counter magnetic layer, and a first nonmagnetic layer provided between the first magnetic layer and the first counter magnetic layer. A direction from the first counter magnetic layer toward the first magnetic layer is along a first direction. The first wire extends in a second direction crossing the first direction. The first magnetic part includes a first region and a first counter region. At least a portion of the first wire is between the first region and the first counter region in the first direction.