Frequency Converter
Convert hertz, kilohertz, megahertz, gigahertz and RPM.
Popular Frequency conversions
All Frequency units
About Frequency
Frequency covers five units and it is the category electronics, audio and computing all draw on. Hertz is the base unit, one cycle per second, and it is what audio frequencies, mains supply and screen refresh rates are measured in. Kilohertz covers radio bands and audio sampling. Megahertz and gigahertz describe processor clocks, memory speeds, radio and wireless bands. RPM, revolutions per minute, measures things that physically spin: engines, drives, fans and motors. People land here to read a spec sheet, compare a component, tune an instrument, check a monitor refresh rate or work with a motor rating. The pages used most are megahertz to gigahertz, gigahertz to megahertz, hertz to kilohertz and hertz to RPM.
The useful orientation is that frequency simply counts how many times something repeats in a given period, which is why the hertz family and RPM belong together even though they look unrelated. Hertz counts cycles per second; RPM counts revolutions per minute. They are the same idea measured against a different clock, which is why converting between them involves the time base as well as the count, and why you cannot just move a decimal point. The hertz units themselves are refreshingly well behaved: unlike digital storage, the prefixes here are plainly decimal, so each step from hertz to kilohertz to megahertz to gigahertz is a clean factor of a thousand with no ambiguity to worry about. The trap in this category is a different one. A higher clock frequency does not automatically mean better performance. Processor gigahertz figures are only comparable within the same architecture, because how much work a chip does per cycle varies enormously between designs. Converting a clock speed tells you the number; it does not tell you which component is faster. The same caution applies to comparing an engine's RPM against another engine.
Every pair page shows the formula used, gives a worked example, and lists a reference table of common values. The pages are free, need no account, and run entirely in your browser, so nothing you enter is uploaded. If you are measuring how long a cycle takes rather than how often it repeats, the time converter is the companion hub.
Frequently asked questions
How does RPM relate to hertz?
Both count repetitions, but against different time bases. Hertz counts cycles per second, while RPM counts revolutions per minute. So converting between them means accounting for the minute as well as the count, which is why it is not a simple decimal shift. The hertz to RPM page and its reverse handle it, and they are useful whenever you have a motor rated one way and a controller specified the other.
Do the hertz prefixes use 1000 or 1024?
They use 1000. Frequency prefixes are plainly decimal, so each step from hertz to kilohertz to megahertz to gigahertz is a clean factor of a thousand with no ambiguity at all. The 1024 confusion belongs to digital storage, where two conventions coexist. Frequency has no such problem, which makes these conversions unusually simple.
Does a higher gigahertz figure mean a faster processor?
Not reliably. Clock speed only tells you how many cycles per second a chip runs, not how much work it completes in each one, and that varies a lot between architectures. A lower-clocked modern chip routinely outperforms a higher-clocked older one. Comparing gigahertz is only meaningful within the same family of processors, so treat a converted clock speed as one figure among several rather than a verdict.
What is a monitor refresh rate measured in?
Hertz. A refresh rate tells you how many times per second the display redraws the image, so a higher hertz figure means smoother motion. Because refresh rates sit in a small range, they are almost always quoted in plain hertz rather than kilohertz. The hertz pages here will convert one if you need it in another unit, though for displays the raw hertz value is what you normally want.