Temperature (sometimes called thermodynamic temperature) is a measure of the average kinetic energy of a systems particles. Temperature is the degree of "hotness" ( or "coldness"), a measure of the heat intensity.
When two objects of different temperatures are in contact, the warmer object becomes colder while the colder object becomes warmer. It means that heat flows from the warmer object to the colder one.
Convert between oC (Celcius), oF (Fahrenheit), K (Kelvin) and oR (Rankine) with the calculator below:
Add the Temperature Converter Web App to your mobile device or desktop. The App is saved in your browser and works offline on newer devices.
A thermometer can help us determine how cold or how hot a substance is. Temperatures in science (and in most of the world) are measured and reported in degrees Celsius (oC). In the U.S., it is common to report temperature in degrees Fahrenheit (oF). On both the Celsius and Fahrenheit scales the temperature at which ice melts (water freezes) and the temperature at which water boils, are used as reference points.
On the Celsius scale there are 100 degrees between freezing point and boiling point of water, compared to 180 degrees on the Fahrenheit scale. This means that 1 oC = 1.8 oF.
Thus the following formulas can be used to convert temperature between the two scales:
tF = 1.8 tC + 32 = 9/5 tC + 32 (1)
tC = 0.56 (tF - 32) = 5/9 (tF - 32) (2)
tC = temperature (oC)
tF = temperature (oF)
Degree Celsius and degree Fahrenheit compared:
Example - A patient with SARS (Severe Acute Respiratory Syndrome) has a temperature of 106 oF. What is the temperature in Celsius?
tC = 5/9 (106 - 32) = 41.1 oC
Another scale (common in science) is Kelvin, or the Absolute Temperature Scale. On the Kelvin scale the coldest temperature possible, -273 oC, has a value of 0 Kelvin (0 K) and is called the absolute zero. Units on the Kelvin scale are called Kelvins (K) and no degree symbol is used.
Because there are no lower temperatures than 0 K - the Kelvin scale does not have negative numbers.
The Kelvin has the same incremental scale as the Celcius scale and one unit Kelvin is equal in size to one unit Celsius:
1 unit Kelvin = 1 unit oC
To calculate a Kelvin temperature, add 273 to the Celsius temperature:
tK = tC + 273.16 (3)
Example - What is the normal body temperature of 37 oC in the Kelvin scale?
tK = tC + 273.16 = 37 + 273.16
= 310.16 K
In the English system the absolute temperature is in degrees Rankine (R), not in Fahrenheit:
tR = tF + 459.67 (4)