Aisha K.
Mar 12, 2026
Clean layout and the results update instantly. Exactly what I needed for a quick planning check.
Unit Converters
Réaumur to Celsius Converter (°Ré to °C)
°C = °Ré × 5/4. Boiling is 80 °Ré, not 100.
Old European cheese caves and Alpine recipes still print °Ré. Water freezes at 0 °Ré and boils at 80 °Ré. Multiply by 5/4 to get Celsius. 80 °Ré is 100 °C, not a medium-rare steak.
Réaumur
°Ré → °C
100 °C
80 °Ré → 100 °C. 16 °Ré cellar → 20 °C.
- You typed
- 80 °Ré
- How it’s calculated
- °C = °Ré × 5/4. Boiling is 80 °Ré, not 100.
Plain-English guide
Terms & how it works
Confused by a field? Read the short definitions here while you use the tool.
Réaumur
The “Réaumur” value used in this tool’s formula. Adjust it to see results update live.
How this calculator works
Old European cheese caves and Alpine recipes still print °Ré. Water freezes at 0 °Ré and boils at 80 °Ré. Multiply by 5/4 to get Celsius. 80 °Ré is 100 °C, not a medium-rare steak. °C = °Ré × 5/4. Boiling is 80 °Ré, not 100. Example: 80 °Ré → 100 °C. 16 °Ré cellar → 20 °C.
°C = °Ré × 5/4. Boiling is 80 °Ré, not 100.
Example: 80 °Ré → 100 °C. 16 °Ré cellar → 20 °C.
When to use this Réaumur to Celsius
Common use cases
- Old European cheese caves and Alpine recipes still print °Ré. Water freezes at 0 °Ré and boils at 80 °Ré. Multiply by 5/4 to get Celsius. 80 °Ré is 100 °C, not a medium-rare steak.
- Sanity-check with this case: 80 °Ré → 100 °C. 16 °Ré cellar → 20 °C.
- The relationship is: °C = °Ré × 5/4. Boiling is 80 °Ré, not 100.
Localized examples
- Unit Converters: the example on this page uses the same formula as the widget.
What you get
- Fields: Réaumur
- °C = °Ré × 5/4. Boiling is 80 °Ré, not 100.
- Example on the page: 80 °Ré → 100 °C. 16 °Ré cellar → 20 °C.
How to Convert Réaumur to Celsius Step-by-Step
- 1Enter Réaumur. Use the values you have, not a catalog average, unless that is all you know.
- 2°C = °Ré × 5/4. Boiling is 80 °Ré, not 100.
- 3Worked case: 80 °Ré → 100 °C. 16 °Ré cellar → 20 °C.
- 4Check which dictionary the other person is using — US or UK, decimal or 1,024 — then trust the number.
Governing formula
°C = °Ré × 5/4. Boiling is 80 °Ré, not 100.
80 °Ré → 100 °C. 16 °Ré cellar → 20 °C.
Example: set Réaumur = 80, then read the result.
Variable definitions
- value
Réaumur
The “Réaumur” field. Default 80; typical range -218.52–2000.
- The conversion (°C = °Ré × 5/4. Boiling is 80 °Ré, not 100.) does not pick US vs UK gallons, SI vs binary megabytes, or Mach at altitude for you. Read the footnote on the page.
- Nothing here is uploaded for the calculation itself.
Frequently Asked Questions
Rarely, outside heritage dairy notes. Convert, then cook in °C.
Related calculators
Unit Converters
- Celsius Heat Units to JoulesA Celsius heat unit is the heat to raise 1 pound of water by 1 °C — about 1,899 J. Old HVAC and process papers use CHU. If you expected BTU, you are on the Fahrenheit twin (1 lb × 1 °F). Do not mix them in a load calc.
- Celsius to FahrenheitWeather apps, ovens, and fever debates. Multiply °C by 9/5 and add 32. Room temperature 20 °C is 68 °F. Body temperature 37 °C is 98.6 °F. The “times two plus 30” trick is only for sidewalks.
- Celsius to KelvinLabs and gas laws want kelvin because zero means zero motion, not “really cold in Celsius.” Add 273.15. You never write a degree sign on K. 25 °C room temp is 298.15 K.
- Celsius to RankineWhen a US customaries thermodynamics problem wants an absolute temperature but you measured Celsius: convert to kelvin, then × 9/5. 20 °C is 527.67 °R. Absolute zero is 0 °R on both sides of the ocean.
- Fahrenheit to CelsiusUS thermostats still speak Fahrenheit. Science and most of the planet speak Celsius. Subtract 32, then multiply by 5/9. 72 °F indoors is 22.2 °C, not “22 unless you like arguing about hoodies.”
- Gas Mark to CelsiusUK Gas Mark 4 is 180 °C (350 °F), the everyday sponge setting. Mark 6 is 200 °C. Fan ovens usually want 15–20 °C less than a still oven. The thermostat in the door is not a lab probe.
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Reviews & Ratings
See what others think about this tool, then leave your own rating to help improve CalculioHub.
4.8
out of 5.0
4 reviews
Daniel R.
Feb 28, 2026
Very usable on mobile. Would love a save/export option later, but the math feels solid.
Priya S.
Feb 3, 2026
The FAQ section answered my questions before I even had to search. Smooth dark mode too.
Marcus L.
Jan 19, 2026
Simple inputs, clear outputs. This replaced three bookmarks I used to juggle.
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