Formula to Calculate Fahrenheit to Celsius, Kelvin Scales

Conversions and calculations can be quite messy when it comes to the Fahrenheit and Celsius scales. Everyone is in search of the easiest way to convert temperature according to the scale they need. Fahrenheit scale has replaced the Celsius scale in the past few years. It is widely used for many applications, especially in the United States. The Internet has now made it easy for every one of us to calculate the Fahrenheit and celsius conversions, but is it possible for us to do the conversions without internet? It is quite difficult for us to memorize the formulas for each an every form of conversion. So let us go through some facts and formulas of these much-needed conversions.

Importance – 

Fahrenheit and Celsius are the most widely used scales around the globe. While Celsius is used in most of the countries, Fahrenheit is used mostly by the Americans. It is important for various applications like the weather forecast, checking body temperature or water temperature, cooking food in the oven, etc. All the other developed countries have adopted the celsius metric system. 


Fahrenheit Vs Celsius 

Fahrenheit is the measurement of temperature in which 32 degrees represents the freezing point of water and 212 degrees represents the boiling point of water. In the case of Celsius measurement, 0 degrees is the freezing point and 100 degrees is the boiling point of water at standard atmospheric pressure. Daniel Gabriel Fahrenheit, a Dutch-German-Polish physicist invented the Fahrenheit scale in 1724. The Celsius scale was developed by Andres Celcius, a Swedish astronomer in 1742. Besides the United States, Cayman Islands, Bahama, Palau, Belize use the Fahrenheit scale. Most other developed countries including Canada are using the most praised Celsius metric scale on a daily basis. 98.6 degrees is the normal body temperature in Fahrenheit scale and 37 degrees is considered as normal in the standard celsius metric scale.


Quick formulas – 

Follow the easy formulas given below for converting the temperature scales according to your needs.

  1. For converting the temperature from Fahrenheit to Celsius, subtract 32 from your temperature number and multiply the result with 5. Divide the result with 9 to obtain your final answer.

Example: if you want to convert 104 degrees Fahrenheit to celsius, do it this way. 

104 – 32 = 72

72 * 5 = 360

360/9 = 40

Hence, 40 is your answer. 

104 degrees Fahrenheit is equal to 40-degree celsius. 


  1. Now to convert the temperature from Celsius to Fahrenheit multiply your number with 9 and divide your answer with 5. Add 32 to your result to get the final answer.

Example: if you want to convert 55 degrees Celsius to Fahrenheit, follow this method.

55 * 9 = 495

495/5 = 99

99 = 32 = 131

Therefore, 131 is your answer.

55-degree celsius is equal to 131 degrees Fahrenheit.


  1. For converting the temperature from Fahrenheit to Kelvin scale, subtract 32 from your temperature number and multiply the resulting number with 5. Now divide by 9 and add 273.15 to your answer to get the final result. 

Example: to convert 121-degree Fahrenheit to kelvin, look for the steps below.

120 – 32 = 88

88 * 5 = 440

440 /9 = 104.8

104.8 + 273.15 = 322.039

322.039 is your result, which means, 120 degrees Fahrenheit is equal to 322.039 kelvin.


  1. To convert the temperature from Kelvin scale to Fahrenheit scale, subtract you number with 273.15, multiply your answer with 1.8 and add 32 to the resulting number to get your final answer.

Example: convert 275 kelvin to Fahrenheit in the following manner.

275 – 273.15 = 1.85

1.85 * 1.8 = 3.33

3.33 + 32 = 35.33 

So here is your answer. 275-degree kelvin is equal to 35.33 Fahrenheit.


  1. Conversion formulas between celsius and kelvin are quite simple compared to the other ones. If you want to convert the temperature from Celsius to Kelvin, add 273 to your number to get the final answer.

Example: to convert 15-degree celsius to kelvin, follow this simple step.

15 + 273 = 288

Thus, 15-degree celsius equals to 288 kelvin.


  1. In case you want to convert the temperature from Kelvin scale to the Celsius scale, subtract 273 to the existing number and you will get the result.

Example: to convert 320-degree kelvin to celsius as follows.

320 – 273 = 47 

Which means, 320 kelvin is equal to 47 degrees celsius.

Leave a Comment