A kilohertz (abbreviated as ” kHz “) is around 1,000-hertz. Like Hertz, kilohertz is also used to measure frequency, or cycles per second. Since one hertz is one cycle per second, so one kilohertz is about 1,000 cycles per second.
Kilohertz is used to measure frequencies of sound waves, since the audible spectrum has sound frequencies between about 20 Hz to 20 kHz.
For example, middle C (C4) produces a piano keyboard with a frequency of about 261.63 Hz. Whereas the C key is above the two octaves that produce the middle C (C6), it produces a frequency that is more than just 1 kHz (1,046.5 Hz).
Since the sound frequency is double with each octave, the C7 key produces an audible frequency that is just more than 2 kHz (2,093 Hz). Now you must have guessed that frequencies which are higher than 2 kHz sound are actually more high-pitched.
Sound waves and low-frequency radio waves are often measured in kilohertz. Other waves, such as high-frequency radio waves, visible light waves, and ultraviolet rays, are all found in higher frequencies. So most waves, in an electromagnetic spectrum, are measured by megahertz, gigahertz , or larger units of measurements.