A switch device may include a rotatable knob provided to be rotatable around a first axis and capable of swinging around a second axis in parallel with the first axis. The switch device may also include a magnet disposed coaxially with the second axis and configured to rotate in conjunction with rotation of the rotatable knob. The switch device may also have a magnetic sensor provided on a fixed-side member and disposed to face an outer periphery of the magnet. The switch device may further include a gear train configured to transmit the rotation of the rotatable knob to the magnet.