A display device includes a display panel, a gate driver, a gate clock signal modulating unit, and a gate clock signal generator. The display panel includes gate lines and pixels connected to the gate lines via respective switching elements. The gate driver includes stages configured to output gate signals to the gate lines. The gate clock signal modulating unit is configured to modulate an input gate clock signal based on a scanning start signal to generate an output gate clock signal. The gate clock signal generator is configured to generate a clock signal based on the gate clock signal and output the clock signal to the gate driver. The gate clock signal modulating unit is configured to modulate a width of a pulse of the input gate clock signal overlapping a pulse of the scanning start signal.