Rankine to Fahrenheit (°R to °F)
1 degree Rankine equals -458.67 degrees Fahrenheit.
How to convert degrees Rankine to degrees Fahrenheit
Converting degrees Rankine to degrees Fahrenheit is not a simple multiplication, so use the formula below.
°F = °R × 1 − 459.67
Example: 10 degrees Rankine = -449.67 degrees Fahrenheit.
Temperature scales have different zero points, so converting is not just multiplication. Differences in degrees convert differently from absolute readings.
About these units
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
Degree Fahrenheit (°F)
The temperature scale used in the United States and a few other countries: water freezes at 32 °F and boils at 212 °F. Proposed by Daniel Gabriel Fahrenheit in 1724.
Daniel Gabriel Fahrenheit, who lived from 1686 to 1736, proposed his scale in 1724. His zero came from a freezing mixture of ice, water and ammonium chloride (or sea salt), which holds a stable temperature, and his upper reference of about 96 was his estimate of human body temperature. His own letters say he built on Ole Rømer's scale. Accounts of how he picked zero differ, and a popular German story that it was the coldest winter day in his home city of Danzig has failed verification.
Around 1776 to 1777 a Royal Society committee led by Henry Cavendish fixed water's freezing point at 32 degrees and its boiling point at 212, exactly 180 degrees apart, which moved body temperature to about 98.6. Today the scale is defined through the kelvin; NIST puts absolute zero at minus 459.67 degrees Fahrenheit. It remains in everyday use in the United States and its territories, Palau, the Federated States of Micronesia, the Marshall Islands and the Cayman Islands. A comfortable room is around 70 degrees, which is about 21 degrees Celsius.
0 degrees Fahrenheit = 255.3722222 kelvins (approximately).
Sources: Wikipedia: Fahrenheit; NIST: the kelvin and the SI redefinition; NIST Guide to the SI, Appendix B.8: conversion factors
Related conversions
- Fahrenheit to Rankine (reverse)
- Rankine to kelvin
- Rankine to Celsius
- Kelvin to Fahrenheit
- Celsius to Fahrenheit
- Réaumur to Fahrenheit
- Delisle to Fahrenheit
- Newton to Fahrenheit
- Rømer to Fahrenheit
See all temperature units.