Temperature
°Rto°C
Convert degrees Rankine (°R) to degrees Celsius (°C).
Converter
°R
Accepts numbers or expressions, e.g. 150 + 14.7
Result
°C
Rendered to 6 significant figures.
Formula
Formula
°C = °R × 5⁄9 − 273.15
Temperature conversions involve different scale zero-points, so a single multiplicative factor does not exist. Apply the formula to each value individually.
Worked example
Convert 540 °R to °C.
- 01540 × 5⁄9 = 300.0000
- 02300.0000 − 273.15 = 26.8500 °C
Result540 °R = 26.85 °C
Conversion table
| °R | °C |
|---|---|
| 0 | -273.15 |
| 100 | -217.59 |
| 300 | -106.48 |
| 491.67 | 5.6843e-14 |
| 540 | 26.85 |
| 600 | 60.183 |
| 800 | 171.29 |
| 1000 | 282.41 |
| 1500 | 560.18 |
| 2000 | 837.96 |
Reference values rounded to 5 significant figures for display.
FAQ
What is the formula to convert °R to °C?
Temperature conversions are not a single multiplier because the scales have different zero points. Use °C = °R × 5⁄9 − 273.15 to convert any value of °R to °C.
How do I convert 1 °R to °C?
1 °R corresponds to -272.594 °C. Apply the formula °C = °R × 5⁄9 − 273.15 to your value.
How do I convert °C back to °R?
Use the inverse formula. For example, to go from °C back to °R, rearrange °C = °R × 5⁄9 − 273.15 for °R. See the °C to °R page for the direct formula.
When would I need to convert degree Rankine to degree Celsius?
Temperature scale conversions are routine in process engineering: instrumentation often reads in °C or °F, while thermodynamic calculations (gas laws, enthalpy) require absolute units (K or °R). Always use absolute units for any equation involving a ratio of temperatures.
Is the conversion exact?
Yes — the temperature scale relationships are exact by definition (the Celsius–Kelvin offset is 273.15 exactly; the Fahrenheit–Rankine offset is 459.67 exactly).