How do you convert Kelvin to Reaumur?

Use the formula Re = (K - 273.15) x 4/5. At the freezing point of water: 273.15 K = 0 Re. At the boiling point: 373.15 K = 80 Re.

When would you need to convert Kelvin to Reaumur?

This conversion is needed when interpreting historical scientific records, comparing temperature data across different measurement traditions, or completing engineering calculations that mix temperature scales from different national standards.

What are the key reference points for both scales?

Water freezes at 273.15 K = 0 Re. Water boils at 373.15 K = 80 Re. These two fixed points anchor both scales and provide easy verification of any conversion calculation.

Kelvin to Réaumur (K to °Ré) Converter

1 K = -217.72 °Ré

1 Kelvin equals -217.72 Réaumur (1 K = -217.72 °Ré). Convert Kelvin to Réaumur with formula, table, and examples.

To convert Kelvin to Reaumur, use the formula: Re = (K - 273.15) x 4/5. The Kelvin scale is the absolute SI temperature unit used in science worldwide, while the Reaumur scale is the historical European scale once standard in France and Germany. Water freezes at 273.15 degrees K (0 Re) and boils at 373.15 degrees K (80 Re).

How to Convert Kelvin to Réaumur

K via Kelvin to °Ré

Formula: Kelvin to Réaumur

Convert to Kelvin: K = K
Convert to Réaumur: °Ré = (K - 273.15) * 4 / 5
Read the result in Réaumur

Common Kelvin to Réaumur Conversions

Kelvin (K)	Réaumur (°Ré)	Status
0 K	-218.52 °Ré
4 K	-215.32 °Ré
20 K	-202.52 °Ré
77 K	-156.92 °Ré
100 K	-138.52 °Ré
173 K	-80.12 °Ré
200 K	-58.52 °Ré
233 K	-32.12 °Ré
253 K	-16.12 °Ré
273.15 K	0 °Ré
293 K	15.88 °Ré
298 K	19.88 °Ré
300 K	21.48 °Ré
310 K	29.48 °Ré
373.15 K	80 °Ré
400 K	101.48 °Ré
500 K	181.48 °Ré
1,000 K	581.48 °Ré
5,000 K	3,781.48 °Ré
10,000 K	7,781.48 °Ré

Good to Know About Kelvin to Réaumur Conversion

The history of temperature measurement is the history of scientific collaboration and competition across borders. The Kelvin scale (the SI standard for thermodynamics) and the Reaumur scale (once widespread in continental Europe) represent different national contributions to solving the same fundamental problem: how to assign numbers to the sensation of hot and cold.

Kelvin to Réaumur: What You Need to Know

The Kelvin scale was created by Lord Kelvin (William Thomson), 1848, the SI standard for thermodynamics. The Reaumur scale was created by Rene Antoine Ferchault de Reaumur, 1730, once widespread in continental Europe. Converting between them bridges different eras and different measurement philosophies in the history of thermometry.

What is a Kelvin? K

The SI base unit of temperature. 0 K is absolute zero, the theoretical lowest possible temperature. Used in science and engineering.

Metric physics chemistry engineering

Learn more about Kelvin →

What is a Réaumur? °Ré

A historical temperature scale where water freezes at 0 °Ré and boils at 80 °Ré. Named after René Antoine Ferchault de Réaumur. Once widely used in Europe.

Historical historical cheese making European history

Learn more about Réaumur →

Going the other way? Use our Réaumur to Kelvin converter.

Kelvin to Réaumur FAQ

Use the formula Re = (K - 273.15) x 4/5. At the freezing point of water: 273.15 K = 0 Re. At the boiling point: 373.15 K = 80 Re.
This conversion is needed when interpreting historical scientific records, comparing temperature data across different measurement traditions, or completing engineering calculations that mix temperature scales from different national standards.
Water freezes at 273.15 K = 0 Re. Water boils at 373.15 K = 80 Re. These two fixed points anchor both scales and provide easy verification of any conversion calculation.

Non-Frequently Asked Questions About Kelvin to Réaumur

Questions nobody should ask - but someone did.

Charming historically, frustrating practically. Reaumur's 0-to-80 range for liquid water is elegant in its own way, but every thermodynamic equation would need modified constants. Kelvin aligns with the fundamental physics of energy and entropy. Reaumur aligns with the practical experience of boiling water. Physics chose Kelvin; cooking chose neither.
Helium liquefies at about 4.2 Kelvin, which is approximately -215.16 degrees Reaumur. This deeply negative Reaumur number shows why the scale was never adopted for cryogenic science. Reaumur works well for the kitchen range of 0 to 80 but produces absurd numbers at the extremes that modern science routinely explores.
It bridges an absolute thermodynamic scale (Kelvin) with a domestic empirical scale (Reaumur). One was designed for calculating the entropy of black holes; the other for checking if your soup is warm enough. The mismatch is not mathematical - the conversion works perfectly - but philosophical. These scales were designed for completely different relationships with temperature.