How to Use It?
To use the calculator, simply enter the temperature value against the given unit field, and the calculator will convert the temperature to different units and display it in the respective input boxes.
Temperature Scales
Temperature scales are developed to standardize and quantify temperature measurement. They provide a consistent and universal way to express the degree of hotness or coldness of an object or environment. Different temperature scales have been developed based on different reference points and historical conventions.
The commonly used temperature scales are Celsius, Fahrenheit, Kelvin, and Rankine.
Fahrenheit Scale (°F):
The Fahrenheit scale is commonly used in the United States and a few other English-speaking countries. It is based on one proposed in 1724 by the physicist Daniel Gabriel Fahrenheit. On this scale, 32°F is defined as the freezing point of water, and 212°F is defined as the boiling point of water. The Fahrenheit scale has 180 equal divisions between these two points.
Celsius Scale (°C):
The Celsius scale is a popular temperature scale that is used in almost all countries that have adopted the metric system of measurement. It was developed by Anders Celsius in 1742, who reversed the Fahrenheit scale and set the freezing point of water at 0°C and the boiling point at 100°C. This scale is also known as the centigrade scale because it divides the temperature range between the freezing and boiling points of water into 100 equal parts.
Kelvin Scale (K):
The Kelvin scale is an absolute temperature scale commonly used in scientific and engineering applications. It is named after the physicist William Thomson, also known as Lord Kelvin, in 1848, who based it on the Celsius scale but shifted it by −273.15°C so that absolute zero (the lowest possible temperature at which all molecular motion ceases) coincides with 0 K. This scale uses kelvins as the temperature unit rather than degrees. Because the Kelvin scale evolved from the Celsius scale, it has the same size divisions as the Celsius scale, with a difference in the reference point.
Rankine Scale (°R):
The Rankine scale is another absolute temperature scale that is preferred over the Kelvin scale in certain fields of engineering, especially in thermodynamics. It is named after the physicist Macquorn Rankine in 1859, who based it on the Fahrenheit scale but shifted it by −459.67°F so that absolute zero coincides with 0 °R. The Rankine scale uses the same degree intervals as the Fahrenheit scale.
Celsius -vs- Fahrenheit -vs- Kelvin -vs- Rankine
The Kelvin scale is an absolute version of the Celsius scale, while the Rankine scale is an absolute version of the Fahrenheit scale. This means that the zero points on these scales represent a theoretical minimum temperature, so they begin at zero and cannot go any lower.
In contrast, the zero points on the Celsius and Fahrenheit scales were originally based on observable physical phenomena, specifically the freezing point of water. This is why these scales can have negative values.
Formulae for Converting Different Temperature Scales
If you need to convert between Celsius, Fahrenheit, Kelvin, and Rankine, you can find some helpful formulas below.
- Celsius to Fahrenheit: °F = (°C × 9/5) + 32
- Celsius to Kelvin: K = °C + 273.15
- Celsius to Rankine: °R = (°C + 273.15) × 9/5
- Fahrenheit to Celsius: °C = (°F − 32) × 5/9
- Fahrenheit to Kelvin: K = (°F − 32) × 5/9 + 273.15
- Fahrenheit to Rankine: °R = °F + 459.67
- Kelvin to Celsius: °C = K − 273.15
- Kelvin to Fahrenheit: °F = (K − 273.15) × 9/5 + 32
- Kelvin to Rankine: °R = K × 9/5
- Rankine to Celsius: °C = (°R − 491.67) × 5/9
- Rankine to Fahrenheit: °F = °R − 459.67
- Rankine to Kelvin: K = °R × 5/9
