Kelvin to Reaumur Converter
Enter the value that you want to convert kelvin (K) to Reaumur (°r) or Reaumur to kelvin.Also written as K to °R conversion.
1 kelvin = -217.7200000 Reaumur
Formula: °Ré = (K − 273.15) × 4/5
K to °R — kelvin to Reaumur
10 kelvin = -210.52000 Reaumur
Popular Temperature Converters:
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Why Convert Kelvin to Reaumur?
The Kelvin Explained
The Kelvin scale begins at absolute zero (−273.15°C) — the theoretical lowest possible temperature where all molecular motion ceases.
Kelvin (K) is the SI base unit of temperature, essential in physics, chemistry, and engineering. It uses the same increment size as Celsius but starts at absolute zero. Key values: 0 K = absolute zero, 273.15 K = water freezes, 373.15 K = water boils. Kelvin is required for gas law calculations (PV=nRT), thermodynamic efficiency, color temperature in photography/lighting (5500K = daylight), and cryogenic engineering.
Understanding the Reaumur
The Réaumur scale sets water's freezing point at 0° and boiling point at 80°, created by French scientist René Antoine Ferchault de Réaumur in 1730.
Once widely used in Europe (particularly France, Germany, and Russia), the Réaumur scale (°Ré) has been almost entirely replaced by Celsius. However, it persists in some traditional industries: Italian and Swiss cheese-making (specifying milk temperatures during production), some French cooking traditions, and historical weather records. The scale is notable for having only 80 divisions between freezing and boiling, making each Réaumur degree 1.25 Celsius degrees.
Temperature Scales in Context
Temperature conversion is one of the few non-linear unit conversions people encounter daily. Celsius dominates scientific work and most countries, Fahrenheit remains standard in the US for weather and cooking, Kelvin is required in thermodynamics and gas law calculations, and Rankine appears in some US engineering applications. Converting between these scales requires formulas rather than simple multiplication.
kelvin to Reaumur metric conversion table
| 0.01 K | = | -218.51200 °r |
| 0.1 K | = | -218.44000 °r |
| 1 K | = | -217.72000 °r |
| 2 K | = | -216.92000 °r |
| 3 K | = | -216.12000 °r |
| 4 K | = | -215.32000 °r |
| 5 K | = | -214.52000 °r |
| 6 K | = | -213.72000 °r |
| 7 K | = | -212.92000 °r |
| 8 K | = | -212.12000 °r |
| 9 K | = | -211.32000 °r |
| 10 K | = | -210.52000 °r |
| 11 K | = | -209.72000 °r |
| 12 K | = | -208.92000 °r |
| 13 K | = | -208.12000 °r |
| 14 K | = | -207.32000 °r |
| 15 K | = | -206.52000 °r |
| 16 K | = | -205.72000 °r |
| 17 K | = | -204.92000 °r |
| 18 K | = | -204.12000 °r |
| 19 K | = | -203.32000 °r |
| 20 K | = | -202.52000 °r |
| 30 K | = | -194.52000 °r |
| 40 K | = | -186.52000 °r |
| 50 K | = | -178.52000 °r |
| 60 K | = | -170.52000 °r |
| 70 K | = | -162.52000 °r |
| 80 K | = | -154.52000 °r |
| 90 K | = | -146.52000 °r |
| 100 K | = | -138.52000 °r |
| 200 K | = | -58.52000 °r |
| 300 K | = | 21.48000 °r |
| 400 K | = | 101.48000 °r |
| 500 K | = | 181.48000 °r |
| 600 K | = | 261.48000 °r |
| 700 K | = | 341.48000 °r |
| 800 K | = | 421.48000 °r |
| 900 K | = | 501.48000 °r |
| 1000 K | = | 581.48000 °r |
How to Convert K to °R (Kelvin to Reaumur)?
We can convert kelvin to Reaumur by using an example.
Example:
Convert 20 Kelvin to Reaumur?
We know 1 Kelvin = -217.7200000 Reaumur; 1 Reaumur = 274.4000000 kelvin.
20 kelvin = ___°r
20 × -217.7200000 = -202.52000 °r (we know 1 kelvin = -217.7200000 Reaumur)
Answer:
20 kelvin = -202.52000 Reaumur
Kelvin to Réaumur Conversion
Convert through Celsius: first subtract 273.15 (K→C), then multiply by 4/5 (C→Ré):
- Subtract 273.15 from Kelvin to get Celsius.
- Multiply by 4/5 (0.8) to get Réaumur.
- Combined: °Ré = (K - 273.15) × 4/5
Solved Examples
Question 1: Convert 373.15 K (boiling water) to Réaumur.
Solution:
°Ré = (373.15 - 273.15) × 4/5
= 100 × 0.8
Answer: 373.15 K = 80°Ré
Question 2: Convert 293 K (room temp) to Réaumur.
Solution:
°Ré = (293 - 273.15) × 0.8
= 19.85 × 0.8
= 15.88
Answer: 293 K ≈ 15.9°Ré
Practice Questions
Try solving these on your own to test your understanding:
- Convert 310 K to Réaumur. (Answer: 29.5°Ré)
- What is 273.15 K in Réaumur? (Answer: 0°Ré)
- Convert 353 K to Réaumur. (Answer: 63.9°Ré)
Key Takeaways
- °Ré = (K - 273.15) × 4/5.
- 273.15 K = 0°Ré, 373.15 K = 80°Ré.
- Rarely needed — mostly for historical data interpretation.
Kelvin to Reaumur Conversion Formula
°Ré = (K − 273.15) × 4/5
1 kelvin = -217.7200000 Reaumur
1 Reaumur = 274.4000000 kelvin
Frequently Asked Questions
How many Reaumur are in 1 kelvin?
1 kelvin equals -217.72000 Reaumur. Note: Temperature conversion uses a formula, not simple multiplication.
How do I convert kelvin to Reaumur?
Use the conversion formula shown above. For example, -214.52 Reaumur equals 5 kelvin. Temperature scales have different zero points, so a formula (not simple multiplication) is required.
How do I convert Reaumur to kelvin?
Use the reverse formula. 1 Reaumur equals 274.40000 kelvin. See the formula section above for the exact equation.
What is 10 kelvin in Reaumur?
10 kelvin is equal to -210.52000 Reaumur.
What is 100 kelvin in Reaumur?
100 kelvin is equal to -138.52000 Reaumur.