The Fahrenheit temperature scale is used in the U.S. and the Myanmar (formerly Burma) and nowhere else. Fahrenheit was a German (d. 1736) who invented the mercury thermometer. He also devised a temperature scale suitable for where he lived in northern Europe. He felt that negative temperatures were inconvenient and so set 0° to be as cold as it ever gets where he lived. 100° he set to be human body temperature, unfortunately his wife's, who seemed to be above average (98.6°.) In the Fahrenheit scale 32° is the freezing point of water, and 212° is the boiling point.
Celsius, a Swede, lived a little later than Fahrenheit and invented what we now call the centigrade temperature scale. In this scale 0° is the freezing and 100° the boiling point of water. Because
we have
TC = (5/9)(TF - 32)
which yields the following:
For almost all scientific purposes we use the Kelvin scale. We will soon see that 0 K is the lowest possible temperature; and so Fahrenheit's dream of non-negative temperatures was not entirely non-sensical - he just picked the wrong starting point. The Kelvin scale is just shifted relative to the Celsius scale, by 273.15 degrees to be precise:
A temperature interval of 1 K is exactly the same as a temperature interval of 1°C. For further conversions, you may want to consult our conversion javaScript engine.
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