Reaumur to Kelvin Converter
Convert a temperature from the historical Reaumur scale into Kelvin, the SI temperature unit. This calculator first maps Reaumur to Celsius, then shifts the result onto the Kelvin scale.
Formula: K = (degRe x 5/4) + 273.15. To reverse it, use Kelvin to Reaumur.
Conversion path
Reaumur to Celsius: multiply by 5/4. Then Celsius to Kelvin: add 273.15.
Reaumur readings in modern Kelvin records
Reaumur is not a daily-use temperature scale for most modern readers, but it still appears in older instruments, historical documents, and classroom examples. Kelvin is the better target when the number needs to enter an SI-based dataset, scientific note, or calculation workflow.
The conversion is not a guess. The Reaumur scale places water freezing at 0 degRe and boiling at 80 degRe, while Celsius uses 0 C and 100 C for the same interval. That makes Celsius equal to Reaumur multiplied by 5/4. Once the value is in Celsius, Kelvin is found by adding 273.15.
Reference points worth checking
| Reaumur | Kelvin | Meaning |
|---|---|---|
| 0 degRe | 273.15 K | Water freezing point |
| 20 degRe | 298.15 K | A convenient room-temperature check |
| 80 degRe | 373.15 K | Water boiling point |
A safer way to clean up historical temperatures
If you are transcribing an old table, keep the original Reaumur reading in one column and place the Kelvin result in another. That preserves the source while making the record usable in modern comparisons. It is also worth keeping a Celsius column when the document is meant for general readers, because Celsius is easier to recognize than Kelvin outside scientific settings.
For adjacent conversions, use Reaumur to Celsius, Celsius to Reaumur, Celsius to Kelvin, Kelvin to Celsius, Reaumur to Fahrenheit, or browse the temperature converter hub.
Common Reaumur to Kelvin questions
Why does Reaumur to Kelvin need two steps?
Reaumur first has to be rescaled to Celsius because 80 Reaumur degrees match 100 Celsius degrees between water freezing and boiling. After that, add 273.15 to express the temperature in Kelvin.
What is 20 degrees Reaumur in Kelvin?
20 degRe equals 25 C, so the Kelvin value is 298.15 K. This is a useful room-temperature style checkpoint for the converter.
Does Kelvin use a degree symbol?
No. Kelvin is written as K, not degrees K. Reaumur is a degree scale, but Kelvin is the SI unit of thermodynamic temperature.
Is Reaumur still used in modern work?
It is uncommon in everyday modern measurement, but it appears in historical instruments, older European references, archival recipes, and education about temperature scales.