Use this temperature converter to quickly convert between Celsius, Fahrenheit, Kelvin, Rankine, and Réaumur.
Temperature conversion is useful when comparing weather, cooking temperatures, scientific measurements, engineering values, international instructions, and educational problems.
Conversions use standard formulas: 0 °C = 32 °F = 273.15 K. Absolute zero is −273.15 °C (−459.67 °F, 0 K). Values below absolute zero are physically impossible and not accepted.
How to Use This Tool
- Enter the temperature value you want to convert.
- Choose the original temperature unit.
- Review the converted values in the other supported temperature scales.
- Change the input to compare another temperature.
Supported Temperature Units
Celsius (°C)
Celsius is used in most countries for weather, cooking, science, and everyday temperature measurement. Water freezes at 0°C and boils at 100°C under standard atmospheric pressure.
Fahrenheit (°F)
Fahrenheit is commonly used in the United States for weather, cooking, body temperature, and home temperature settings. Water freezes at 32°F and boils at 212°F under standard atmospheric pressure.
Kelvin (K)
Kelvin is commonly used in science and engineering. Kelvin starts at absolute zero, so it does not use negative values in normal physical temperature measurement.
Rankine (°R)
Rankine is an absolute temperature scale based on Fahrenheit degrees. It is used in some engineering and thermodynamics contexts.
Réaumur (°Ré)
Réaumur is a historical temperature scale. It is less commonly used today, but it may appear in older scientific, historical, or regional references.
Common Uses
You can use this temperature converter for:
- Converting Celsius to Fahrenheit
- Converting Fahrenheit to Celsius
- Converting Celsius to Kelvin
- Converting Kelvin to Fahrenheit
- Checking cooking temperature instructions
- Comparing international weather reports
- Working on science homework
- Understanding engineering or thermodynamics values
- Reading historical temperature references
Example
If a recipe says to bake at 180°C and your oven uses Fahrenheit, enter 180 and choose Celsius. The converter will show the equivalent Fahrenheit value.
If a science problem gives a temperature in Kelvin and you need Celsius, enter the Kelvin value and review the Celsius conversion.
Important Temperature Notes
Temperature conversion is different from length or weight conversion because temperature scales often have different starting points. For example, 0°C equals 32°F, not 0°F. Kelvin begins at absolute zero, where 0 K equals -273.15°C.
Values below absolute zero are physically impossible and should not be accepted in normal temperature conversion.
Why Temperature Conversion Matters
Different countries and industries use different temperature systems. A weather report may use Celsius, an oven may use Fahrenheit, and a science equation may require Kelvin.
Using the correct temperature scale helps avoid mistakes in cooking, scientific calculations, engineering work, and international communication.
Frequently Asked Questions (FAQs)
What is the difference between Celsius and Fahrenheit?
Celsius is based around 0°C for freezing water and 100°C for boiling water under standard conditions. Fahrenheit uses 32°F for the freezing point of water and 212°F for the boiling point of water under standard conditions.
What is Kelvin used for?
Kelvin is used in science and engineering because it is based on absolute zero.
Can Kelvin be negative?
In ordinary physical temperature measurement, Kelvin cannot go below 0 K because 0 K is absolute zero.
What is absolute zero?
Absolute zero is the lowest theoretical temperature, equal to 0 K, -273.15°C, or -459.67°F.
Why is temperature conversion not just multiplication?
Some temperature scales have different zero points, so formulas often require adding or subtracting a value as well as multiplying.
Disclaimer
This temperature converter is provided for general informational and convenience purposes only. Users should verify important temperature values before using them for cooking safety, laboratory work, engineering, medical decisions, industrial processes, or official requirements.