An object of the present invention is to provide an input device, a biosensor, a program, a computer-readable medium, and a mode setting method that enable errors in determining whether or not to set a mode of a control target device to be controlled to be reduced. An input device includes: a sensor signal acquisition unit configured to acquire a sensor signal; a waveform comparison unit configured to compare waveforms during two or more periods of the sensor signal; and a mode setting unit configured to, on the basis of a result of comparison by the waveform comparison unit, set a mode of a control target device to be controlled.