Réaumur to Kelvin Converter

Réaumur (°Ré or °R) is a temperature scale where 0°Ré is the freezing point of water and 80°Ré is the boiling point of water at standard atmospheric pressure. Each degree Réaumur equals 1.25 degrees Celsius.

The Réaumur scale was developed by French scientist René Antoine Ferchault de Réaumur in 1730. He chose 80 degrees between the freezing and boiling points of water because his alcohol-based thermometer expanded by 80 parts per 1000 when heated from freezing to boiling water.

The Réaumur scale is largely obsolete and rarely used today. It may occasionally appear in historical scientific documents, some traditional European recipes (particularly in Germany and Russia), and certain specialized industrial applications. Most modern applications have switched to Celsius or Fahrenheit.

Kelvin (K) is the base unit of thermodynamic temperature in the International System of Units (SI). It is an absolute temperature scale where 0 K represents absolute zero, the theoretical point where all molecular motion ceases.

The Kelvin scale was developed by British physicist William Thomson, 1st Baron Kelvin, in 1848. It was based on the Celsius scale but shifted to start at absolute zero (-273.15°C). In 2019, the kelvin was redefined using the Boltzmann constant, making it more precise and fundamental.

Kelvin is the standard temperature unit in scientific research, particularly in physics, chemistry, and astronomy. It's used in thermodynamics, quantum mechanics, stellar astronomy, and any scientific work requiring absolute temperature measurements. It's essential for gas laws and thermal physics calculations.