Guide to Celsius To Reaumur

Celsius to Reaumur: A Temperature Scale Most People Forgot

The Reaumur scale may not be part of everyday conversation, but it holds an important place in scientific history and still appears in certain European industries today. This Celsius to Reaumur converter lets you translate temperatures between these two scales instantly, whether you are studying historical scientific literature, working in food production, or just satisfying your curiosity.

What Is the Reaumur Scale?

Invented by French scientist Rene Antoine Ferchault de Reaumur in 1730, the Reaumur scale sets the freezing point of water at 0 degrees and the boiling point at 80 degrees. Compare this to Celsius, which uses 0 and 100 for the same reference points. The two scales share the same zero point but differ in the size of each degree. A Reaumur degree is 1.25 times larger than a Celsius degree.

The conversion formula is straightforward: Reaumur = Celsius x 0.8. Or equivalently, Celsius = Reaumur x 1.25. This Celsius to Reaumur converter applies these formulas precisely for any temperature you enter, positive or negative.

Where Reaumur Is Still Used

While most of the world has standardized on Celsius (and the US on Fahrenheit), the Reaumur scale persists in a few niches. Italian and French cheese makers sometimes use Reaumur when following traditional production methods that predate the widespread adoption of Celsius. Certain historical brewing and distilling texts also reference Reaumur temperatures.

In the Netherlands and parts of Germany, older industrial thermometers calibrated in Reaumur can still be found in sugar refineries and chocolate factories, where production processes were originally developed using this scale. When maintaining or replicating these traditional processes, converting between Celsius and Reaumur accurately is essential.

Historical Significance

The Reaumur scale was the dominant temperature scale in much of Europe throughout the 18th and 19th centuries, particularly in France, Germany, and Russia. It was the scale used in many foundational scientific papers and industrial standards. Reading historical scientific literature often requires converting Reaumur temperatures to Celsius to understand the experimental conditions described.

Russia used the Reaumur scale well into the early 20th century. Many Russian literary and scientific works from that era reference temperatures in Reaumur, and understanding those references requires knowing the conversion. Tolstoy, Dostoevsky, and Chekhov all described weather in Reaumur degrees.

Quick Reference Conversions

Some useful Celsius to Reaumur benchmarks: 0 degrees Celsius = 0 degrees Reaumur (freezing point of water). 20 degrees Celsius (comfortable room temperature) = 16 degrees Reaumur. 37 degrees Celsius (human body temperature) = 29.6 degrees Reaumur. 100 degrees Celsius (boiling water) = 80 degrees Reaumur. -40 degrees Celsius = -32 degrees Reaumur.

Educational Value

Studying multiple temperature scales, including Reaumur, deepens understanding of how measurement systems work. The fact that any linear temperature scale can be defined by two fixed points and an arbitrary number of divisions between them is a fundamental concept in metrology. Comparing Celsius, Fahrenheit, Kelvin, Rankine, and Reaumur illustrates this principle beautifully.

This Celsius to Reaumur converter is free, browser-based, and always available. Whether your interest is historical, academic, or industrial, bookmark it for the next time you encounter this venerable temperature scale.

Try the Converter Today

Whether you are translating a passage from a 19th-century French physics textbook, maintaining a traditional Italian cheese cave, or simply exploring the diversity of temperature measurement systems, this Celsius to Reaumur converter provides instant, accurate results. It takes just a number and returns the answer you need. No registration, no installation, just reliable temperature conversion at your fingertips whenever the Reaumur scale appears in your work or reading.