Degrees Celsius to Degrees Réaumur
Type a value in Degrees Celsius and get the result in Degrees Réaumur, calculated exactly.
20 Degrees Celsius = 16 Degrees Réaumur
Exact factorThis result is exact.
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Turn either dial: drag it, use the arrow keys, or scroll while it has focus. Both cover the same range.
Range -25 – 50 °C = -20 – 40 °Ré
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Formula
°Ré = °C × 0.8 + 0
To convert Degrees Celsius to Degrees Réaumur, multiply the value by 0.8, then add 0.
Worked examples
- 0 °C = 0 °Ré
- 20 °C = 16 °Ré
- 100 °C = 80 °Ré
This factor is exact by definition.
Conversion table
| Degrees Celsius (°C) | Degrees Réaumur (°Ré) |
|---|---|
| −40 | −32 |
| −30 | −24 |
| −20 | −16 |
| −10 | −8 |
| 0 | 0 |
| 5 | 4 |
| 10 | 8 |
| 15 | 12 |
| 20 | 16 |
| 25 | 20 |
| 30 | 24 |
| 35 | 28 |
| 37 | 29.6 |
| 40 | 32 |
| 50 | 40 |
| 60 | 48 |
| 70 | 56 |
| 80 | 64 |
| 90 | 72 |
| 100 | 80 |
| 150 | 120 |
| 200 | 160 |
Values marked ≈ are rounded; the rest are exact.
Reverse table: Degrees Réaumur to Degrees Celsius
| Degrees Réaumur (°Ré) | Degrees Celsius (°C) |
|---|---|
| −40 | −50 |
| −30 | −37.5 |
| −20 | −25 |
| −10 | −12.5 |
| 0 | 0 |
| 5 | 6.25 |
| 10 | 12.5 |
| 15 | 18.75 |
| 20 | 25 |
| 25 | 31.25 |
| 30 | 37.5 |
| 35 | 43.75 |
| 37 | 46.25 |
| 40 | 50 |
| 50 | 62.5 |
| 60 | 75 |
| 70 | 87.5 |
| 80 | 100 |
| 90 | 112.5 |
| 100 | 125 |
| 150 | 187.5 |
| 200 | 250 |
Unit definitions
- Degrees Celsius °C
- The kelvin scale shifted by exactly 273.15: 0 °C is 273.15 K.
- Degrees Réaumur °Ré
- A historical scale with water freezing at 0 and boiling at 80: one degree is exactly 1.25 °C.
Questions people ask
Degrees Celsius to Degrees Réaumur: what is the conversion factor?
One °C is 0.8 °Ré.
How do I convert Degrees Celsius to Degrees Réaumur?
Use the formula above. For example, 20 °C = 16 °Ré.
Is the conversion exact?
Yes. Both units have exact definitions, so the factor is exact; a result is only rounded when its decimals never end.
Factors checked 19 October 2026.