Rankine is a now rarely used temperature scale named after the Scottish engineer and physicist William John Macquorn Rankine, who proposed it in 1859.

The symbol is °R (note that this symbol is also used to stand for the Rømer and Réaumur scales). Like kelvin, Rankine zero is absolute zero, but Fahrenheit degrees are used. As a result, a difference of 1°R is equal to a difference of 1°F, but 0°R is −459.67°F.

The Rankine cycle is an idealised thermodynamic cycle for a steam engine, i.e. one using water as the working fluid.

See also

• Rankine-Hugoniot equation