Temperature Converter
Convert between Celsius, Fahrenheit, Kelvin, Rankine, and Réaumur.
Celsius
°C
100
Fahrenheit
°F
212
Kelvin
K
373.15
Rankine
°R
671.67
Réaumur
°Re
80
Key Reference Points
Water freezes
0°C · 32°F · 273.15K
Water boils
100°C · 212°F · 373.15K
Body temp
37°C · 98.6°F · 310.15K
Room temp
20°C · 68°F · 293.15K
Absolute zero
-273.15°C · -459.67°F · 0K
About This Tool
Converts temperature values between Celsius, Fahrenheit, Kelvin, Rankine, and Réaumur instantly.
Enter any value in any unit and all other units update immediately. A reference table of key temperatures is shown below the results.
How to Use
- Enter the temperature value in the input field.
- Select the unit of the value you entered (Celsius, Fahrenheit, or Kelvin).
- All conversions update instantly in the results panel.
- Use the reference table to verify common temperature benchmarks.
Use Cases
Scientists converting between Kelvin and Celsius for thermodynamic calculations. Travelers checking local weather in Fahrenheit versus Celsius. Engineers working with cryogenic or high-temperature processes verifying Kelvin and Rankine values.
FAQ
- Why are there 5 output scales? — Celsius, Fahrenheit, and Kelvin cover everyday use and science. Rankine is used in some US engineering fields. Réaumur is a historical scale still referenced in some European texts.
- What is absolute zero? — The lowest possible temperature — 0 K (−273.15 °C / −459.67 °F) — where molecular motion theoretically stops completely.
- Why can I only select Celsius, Fahrenheit, and Kelvin as input? — These three cover the vast majority of real-world input. Rankine and Réaumur are derived from them, so selecting one of the three is sufficient for all outputs.