Temperature Converter
Convert between Celsius (°C), Fahrenheit (°F), and Kelvin (K) in real time. Simply type a value in any field to calculate the conversions instantly.
Understanding Temperature Scales
Temperature is a physical property that quantitatively expresses hot and cold. It is measured with thermometers that can be calibrated to various temperature scales. The three most common units of temperature used in science and everyday life are Celsius, Fahrenheit, and Kelvin.
What is a Degree Celsius (°C)?
Originally known as the centigrade scale, Celsius is a scale based on 0°C for the freezing point of water and 100°C for the boiling point of water at standard atmospheric pressure. Today, it is the primary temperature scale used in most countries and for general scientific calculations.
What is a Degree Fahrenheit (°F)?
The Fahrenheit scale is a thermodynamic temperature scale proposed in 1724 by the physicist Daniel Gabriel Fahrenheit. On this scale, the freezing point of water is 32°F and the boiling point is 212°F, placing the boiling and freezing points exactly 180 degrees apart. It remains primarily used in the United States and its territories.
What is Kelvin (K)?
The Kelvin scale is the absolute thermodynamic temperature scale used in sciences. It is defined such that absolute zero—the theoretical temperature where all thermodynamic motion ceases—is exactly 0 K. It is named after the physicist William Thomson, 1st Baron Kelvin. Because it is an absolute scale, temperatures measured in kelvins do not use the "degree" symbol.
Temperature Conversion Formulas
Use the following formulas to manually convert between the scales:
| From Scale | To Scale | Formula |
|---|---|---|
| Celsius (°C) | Fahrenheit (°F) | (°C × 9/5) + 32 = °F |
| Celsius (°C) | Kelvin (K) | °C + 273.15 = K |
| Fahrenheit (°F) | Celsius (°C) | (°F - 32) × 5/9 = °C |
| Fahrenheit (°F) | Kelvin (K) | (°F - 32) × 5/9 + 273.15 = K |
| Kelvin (K) | Celsius (°C) | K - 273.15 = °C |
| Kelvin (K) | Fahrenheit (°F) | (K - 273.15) × 9/5 + 32 = °F |
Frequently Asked Questions (FAQ)
What is a degree in temperature?
A degree is a unit of measurement used to specify temperature on various scales, such as Celsius (°C) and Fahrenheit (°F). It represents an interval of temperature difference.
How do you convert Celsius to Fahrenheit quickly?
To convert Celsius to Fahrenheit quickly, multiply the Celsius temperature by 1.8 (or 9/5) and add 32. For example, 10°C becomes 10 × 1.8 + 32 = 50°F.
What is the formula for converting Fahrenheit to Kelvin?
To convert Fahrenheit to Kelvin, first subtract 32 from the Fahrenheit temperature, multiply by 5/9, and then add 273.15. The formula is: K = (F - 32) × 5/9 + 273.15.
What is absolute zero in Celsius, Fahrenheit, and Kelvin?
Absolute zero is the lowest possible temperature where all molecular activity stops. It corresponds to 0 K on the Kelvin scale, -273.15°C on the Celsius scale, and -459.67°F on the Fahrenheit scale.
Why does the Kelvin scale not use the degree symbol?
Unlike Celsius and Fahrenheit, Kelvin is an absolute thermodynamic scale, not a relative degree scale. Its unit is the kelvin (symbol: K), which is an absolute unit of measurement similar to meters or seconds.