Celsius to Rankine (°C to °R)
1 degree Celsius equals 493.47 degrees Rankine.
How to convert degrees Celsius to degrees Rankine
Converting degrees Celsius to degrees Rankine is not a simple multiplication, so use the formula below.
°R = (°C + 273.15) × 9/5
Example: 10 degrees Celsius = 509.67 degrees Rankine.
Temperature scales have different zero points, so converting is not just multiplication. Differences in degrees convert differently from absolute readings.
About these units
Degree Celsius (°C)
The metric temperature scale used worldwide for weather and daily life: water freezes at 0 °C and boils at 100 °C at standard pressure. Named after Anders Celsius.
Anders Celsius, a Swedish astronomer, proposed a scale in 1742 that ran the opposite way from the one we use: 0 for the boiling point of water and 100 for its freezing point. Credit for flipping it is shared and partly disputed. French physicist Jean-Pierre Christin published a reversed mercury thermometer in 1743, Carl Linnaeus is usually credited with reversing it in 1744, the year Celsius died, and others in Sweden, including Pehr Elvius, Daniel Ekström and Mårten Strömer, are also named as independent developers.
For much of the nineteenth century the scale was called centigrade, until the CGPM and CIPM adopted the name degree Celsius in 1948, partly to honor Celsius and to avoid confusion with a French term for a subdivision of the gradian. From 1954 to 2019 it was defined through absolute zero and the triple point of water; since 2019 it is tied to the Boltzmann constant. Strictly, water boils at about 99.974 degrees on the modern international temperature scale, not exactly 100. Australian weather reports switched exclusively to Celsius in 1972.
0 degrees Celsius = 273.15 kelvins (exactly).
Sources: Wikipedia: Celsius; BIPM: 9th CGPM (1948), Resolution 7; NIST: the kelvin and the SI redefinition
Degree Rankine (°R)
An absolute scale with Fahrenheit-sized degrees: 0 °R is absolute zero. Used in some engineering thermodynamics.
Scottish engineer and physicist William John Macquorn Rankine of the University of Glasgow proposed this scale in 1859. His idea was simple: keep the size of the Fahrenheit degree but start counting at absolute zero, so that no temperature is ever negative. Zero on the scale is therefore 0 K, which equals about minus 459.67 degrees Fahrenheit, and a reading in Rankine is just the Fahrenheit reading plus 459.67.
Because one Rankine degree is exactly 5/9 of a kelvin, converting is a matter of multiplying by 5/9 or, going the other way, multiplying kelvins by 9/5. NIST states the same relation as kelvin equal to the Rankine value divided by 1.8. Water freezes at 491.67 degrees Rankine and boils at roughly 671.64 degrees on the same scale. The scale appears mainly in some thermodynamics and heat-transfer calculations in US engineering, where data are tabulated in Fahrenheit-sized degrees. Everywhere else, kelvins and Celsius degrees have taken over, and the symbol is sometimes written °Ra to avoid confusion with the Rømer and Réaumur scales.
1 degree Rankine = 0.5555555556 kelvins (approximately).
Sources: Wikipedia: Rankine scale; NIST SP 811, Appendix B.8 conversion factors
Related conversions
- Rankine to Celsius (reverse)
- Celsius to kelvin
- Celsius to Fahrenheit
- Celsius to Réaumur
- Celsius to Delisle
- Celsius to Newton
- Celsius to Rømer
- Kelvin to Rankine
- Fahrenheit to Rankine
See all temperature units.