Convert Rankine (°R) to Reaumur (°r) instantly.
About these units
Rankine (°R)
The Rankine scale is the absolute-temperature counterpart to Fahrenheit, just as kelvin is to Celsius. It starts at absolute zero—0°R—but increments in degrees of the same size as Fahrenheit. This makes Rankine essential for thermodynamic calculations in engineering fields that rely on the imperial system, especially in the United States. Many formulas in gas dynamics, thermodynamics, and aerospace engineering require absolute temperatures, and Rankine serves this purpose without the need to switch to metric units. For example, ideal gas law equations in US customary engineering practice use Rankine directly. Although less commonly referenced outside engineering, the Rankine scale occupies a crucial niche. It preserves consistency with Fahrenheit-based systems while enabling high-level thermodynamic work. Its existence reflects the adaptability of absolute scales to multiple cultural measurement frameworks.
Reaumur (°r)
The Réaumur scale, created by René Antoine Ferchault de Réaumur in 1730, was once a major temperature scale in Europe, particularly in France, Germany, Russia, and parts of Italy. It sets the freezing point of water at 0°r and the boiling point at 80°r, giving it eighty divisions between these points. Réaumur's scale was historically used in cheese-making, brewing, confectionery, textile production, and early scientific experiments. Many recipes and industrial methods from the 18th and 19th centuries reference it. The scale's smaller numeric range made it easy to work with, though it offered less granularity than Celsius. Eventually, the Celsius scale replaced Réaumur almost everywhere due to metric standardization. However, the Réaumur scale's legacy persists in historical documents, culinary traditions, and scientific literature from the Enlightenment era, where it formed a cornerstone of early temperature standardization.