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Celsius to Réaumur (°C to °Ré) Converter

1 °C = 0.8 °Ré

1 Celsius equals 0.8 Réaumur (1 °C = 0.8 °Ré). Convert Celsius to Réaumur with formula, table, and examples.

To convert Celsius to Réaumur, multiply by 4/5. The Réaumur scale sets water's freezing point at 0°Ré and boiling point at 80°Ré. Once widely used in continental Europe, it is now nearly obsolete, surviving only in a few traditional cheese-making and dairy processes.

How to Convert Celsius to Réaumur

°Ré = °C × 4/5
Formula: Celsius to Réaumur
  1. Take your Celsius value
  2. Multiply by 4/5 (or 0.8)
  3. Read the result in Réaumur

Common Celsius to Réaumur Conversions

Celsius (°C) Réaumur (°Ré) Status
-40 °C -32 °Ré
-20 °C -16 °Ré
-10 °C -8 °Ré
0 °C 0 °Ré
5 °C 4 °Ré
10 °C 8 °Ré
15 °C 12 °Ré
20 °C 16 °Ré
25 °C 20 °Ré
30 °C 24 °Ré
36 °C 28.8 °Ré
37 °C 29.6 °Ré
40 °C 32 °Ré
50 °C 40 °Ré
60 °C 48 °Ré
80 °C 64 °Ré
100 °C 80 °Ré
150 °C 120 °Ré
180 °C 144 °Ré
200 °C 160 °Ré
220 °C 176 °Ré
250 °C 200 °Ré
300 °C 240 °Ré
500 °C 400 °Ré
1,000 °C 800 °Ré

Good to Know About Celsius to Réaumur Conversion

The Réaumur scale was used in Germany longer than in France, even though a Frenchman invented it. German meteorological records from the 18th and 19th centuries often require Réaumur-to-Celsius conversion for modern analysis.

Celsius to Réaumur: What You Need to Know

Room temperature of 20°C equals 16°Ré. Body temperature (37°C) is 29.6°Ré. Boiling water (100°C) is 80°Ré. The Réaumur scale was the dominant temperature scale in Germany and France during the 18th and 19th centuries before Celsius replaced it.

What is a Celsius? °C

A metric temperature scale where 0°C is the freezing point and 100°C is the boiling point of water. Used worldwide except in the US.

Metric weather cooking science
Learn more about Celsius →

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 Celsius converter.

Celsius to Réaumur FAQ

  • The formula is: °Ré = °C × 4/5. For example, 25°C × 4/5 = 20°Ré. The Réaumur degree is 1.25 times larger than a Celsius degree.

  • 100°C equals exactly 80°Ré. The Réaumur scale has 80 degrees between freezing and boiling, compared to 100 for Celsius.

  • The Réaumur scale survives only in niche applications, primarily in traditional cheese-making and dairy processes in parts of Switzerland and Italy. Some old recipes specify curdling temperatures in Réaumur.

Non-Frequently Asked Questions About Celsius to Réaumur

Questions nobody should ask - but someone did.

  • Reaumur calibrated his thermometer with the expansion of alcohol mixed with water. The 80-degree range was not chosen for mathematical elegance - it was simply what his thermometer showed. Sometimes science is just 'that is what the instrument said.'

Need the reverse? Use our Réaumur to Celsius converter. See all Temperature converters.