A D-type flip-flop can be configured as a clock divider.
Study of a clock divider, using a D flip-flop (TTL family, 7474).
For a symmetric input, the input and output waveforms are shown below.
The output toggles at every rising edge of the input, resulting in a division of frequency by two. The output is a symmetric squarewave, irrespective of the duty cycle of the input pulse, as shown below. Every rising edge of the input results in a level change at the output.