Orders of magnitude (frequency)

To help compare different orders of magnitude, the following list describes various frequencies.

Examples

10 Hz, cyclic rate of a typical automobile engine at idle (equivalent to 600 rpm)
50 Hz or 60 Hz (50 Hz for European AC, Tokyo AC or 60 Hz for American AC, Osaka AC), electromagnetic — standard AC mains power
20 Hz to ~16 kHz, acoustic — normal range of adult human hearing (most children and some animals perceive sounds outside this range)
100 Hz, cyclic rate of a typical automobile engine at redline (equivalent to 6000 rpm)
261.626 Hz, acoustic — the musical note middle C
440 Hz, acoustic — concert pitch (A above middle C), used for tuning musical instruments
530 kHz to 1.710 MHz, electromagnetic — AM radio broadcasts
740 kHz, transitions — the clock speed of the world's first commercial microprocessor, the Intel 4004 (1971)
1 MHz to 8 MHz, transitions — clock speeds of early home/personal computers (mid-1970s to mid-1980s)
42 MHz to 260 MHz, electromagnetic — VHF terrestrial TV broadcast channels
88 MHz to 108 MHz, electromagnetic — FM radio broadcasts
1420 MHz, the frequency of the hyperfine transition of hydrogen, the most common element in the universe.
3.73 GHz, transitions — clock speed of the Pentium 4 "Prescott" microprocessor (2005)
428 THz to 750 THz, electromagnetic — visible light, from red to violet
30 PHz, electromagnetic — x-rays