Fahrenheit is the name of the “English system” of measuring temperature and Celsius or centigrade is the name of the metric system of measuring temperature. These two systems are the most commonly used scales for measuring temperature. Fahrenheit is usually shortened to “F” and Celsius or centigrade is shortened to “C.” Whenever you read or write a temperature, it must always have a C or an F to show what scale is being used. Most scientists use the Celsius or centigrade scale, and you should become very familiar with it.

Remember, water boils and freezes at the same temperature regardless of what scale is used to measure and describe the temperature. We can describe the freezing point of water as 0º Celsius (0ºC) or as 32º Fahrenheit (32ºF), yet both of these numbers are describing the same actual temperature.

There are some simple formulas to convert from Fahrenheit to Celsius, and from Celsius to Fahrenheit.

To convert from Fahrenheit to Celsius, subtract 32 and divide by 1.8.

°C = (°F -32) / 1.8

To convert from Celsius to Fahrenheit, multiply by 1.8 and add 32.

°F = °C x 1.8 + 32