Temperature Conversion
Celsius ↔ Fahrenheit ↔ Kelvin.
What does Temperature Conversion mean?
Temperature conversion lets you translate a reading from one temperature scale to another. The three most common scales are Celsius (used worldwide for everyday temperatures), Fahrenheit (used primarily in the United States), and Kelvin (the SI base unit used in science). Each scale has different zero points and degree sizes, so converting between them requires specific formulas rather than a simple multiplication.
How to calculate Temperature Conversion
To convert Celsius to Fahrenheit, multiply by 9/5 and add 32: °F = °C × 9/5 + 32. To go the other way, subtract 32 and multiply by 5/9: °C = (°F − 32) × 5/9. For Kelvin, simply add or subtract 273.15 from Celsius: K = °C + 273.15. For example, 100 °C = 212 °F = 373.15 K (the boiling point of water at standard pressure).
FAQ
Absolute zero is 0 K (−273.15 °C or −459.67 °F). It is the lowest possible temperature, where all molecular motion ceases. Nothing can be cooled below this point.
The Fahrenheit scale was developed by Daniel Fahrenheit in 1724 and became widespread in English-speaking countries. While most of the world later adopted Celsius, the US retained Fahrenheit for everyday use due to historical convention.
Celsius and Fahrenheit read the same value at −40°. This is the only point where the two scales intersect: −40 °C = −40 °F.
Kelvin starts at absolute zero and uses the same degree size as Celsius, making it ideal for scientific calculations. Many physics formulas (gas laws, thermodynamics) require an absolute temperature scale to work correctly.
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