A level shifter includes a driving signal generating unit, a driving unit, and a current path forming unit. The driving signal generating unit is configured to generate a pull-up signal and a pull-down signal in response to an input signal, which may swing between a first high level and a first low level. The driving unit is configured to generate an output signal swinging between a second high level and a second low level in response to the pull-up signal and the pull-down signal. The current path forming unit is configured to form a current path between the pull-up signal and the pull-down signal in response to the pull-up signal and the pull-down signal.