Réaumur to Kelvin

Réaumur (°Ré): The Réaumur scale has the freezing point of water at 0 °Ré and the boiling point at 80 °Ré. It was popular in parts of Europe in the 18th and 19th centuries, particularly in France and Germany.

Kelvin (K): The Kelvin scale is the base unit of thermodynamic temperature in the International System of Units (SI). It is an absolute temperature scale, meaning 0 K (absolute zero) is the point where all thermal motion ceases. It has no degrees symbol (°).