Convert Rankine to Celsius
Live bidirectional calculator for Rankine (°R) and Celsius (°C) with verified formula and conversion charts.
Temperature4 units
How the Calculation Works (Affine Transformation)
Subtract 491.67 (freezing point of water in Rankine) and scale by 5/9 to obtain Celsius.
Rankine to Celsius Conversion Table
Precomputed values for quick reference and printing.
| Rankine | Celsius |
|---|---|
| 1 °R | -272.5944 °C |
| 2 °R | -272.0389 °C |
| 3 °R | -271.4833 °C |
| 4 °R | -270.9278 °C |
| 5 °R | -270.3722 °C |
| 6 °R | -269.8167 °C |
| 7 °R | -269.2611 °C |
| 8 °R | -268.7056 °C |
| 9 °R | -268.15 °C |
| 10 °R | -267.5944 °C |
| 15 °R | -264.8167 °C |
| 20 °R | -262.0389 °C |
| 25 °R | -259.2611 °C |
| 30 °R | -256.4833 °C |
| 40 °R | -250.9278 °C |
| 50 °R | -245.3722 °C |
| 75 °R | -231.4833 °C |
| 100 °R | -217.5944 °C |
| Celsius | Rankine |
|---|---|
| 1 °C | 493.47 °R |
| 2 °C | 495.27 °R |
| 3 °C | 497.07 °R |
| 4 °C | 498.87 °R |
| 5 °C | 500.67 °R |
| 6 °C | 502.47 °R |
| 7 °C | 504.27 °R |
| 8 °C | 506.07 °R |
| 9 °C | 507.87 °R |
| 10 °C | 509.67 °R |
| 15 °C | 518.67 °R |
| 20 °C | 527.67 °R |
| 25 °C | 536.67 °R |
| 30 °C | 545.67 °R |
| 40 °C | 563.67 °R |
| 50 °C | 581.67 °R |
| 75 °C | 626.67 °R |
| 100 °C | 671.67 °R |
About Rankine (°R)
The Rankine scale is an absolute temperature scale using Fahrenheit-sized degrees. 0 °R is absolute zero, and 491.67 °R is the freezing point of water.
History: Proposed by William John Macquorn Rankine in 1859. Used primarily in US engineering thermodynamics.
Common Uses: Thermodynamic calculations in US engineering, particularly in HVAC, combustion, and turbine analysis.
About Celsius (°C)
The Celsius scale is defined so that 0 °C is the freezing point of water and 100 °C is the boiling point of water at standard atmospheric pressure.
History: Proposed by Anders Celsius in 1742 (originally inverted). The modern direction was established by Carl Linnaeus. Renamed from "centigrade" to "Celsius" in 1948 by the 9th CGPM.
Common Uses: Daily weather, cooking, scientific measurement, and industrial processes worldwide (except the US for everyday use).
❓ Frequently Asked Questions
What is 1 °R in °C?
1 Rankine (°R) is equal to -272.5944 Celsius (°C). Unlike linear units, temperature scales have differing zero offsets.
What is the formula to convert Rankine to Celsius?
The formula is: °C = (°R - 491.67) × 5/9. Subtract 491.67 (freezing point of water in Rankine) and scale by 5/9 to obtain Celsius.
How do I convert 1 °R to °C manually?
To convert 1 °R to °C: apply the formula °C = (°R - 491.67) × 5/9. Substituting gives: (1 - 491.67) × 5/9 = -272.5944 °C.