kelvincelsius

Kelvincelsius is an informal or nonstandard term that appears in some educational and technical contexts to describe the relationship between the Kelvin and Celsius temperature scales. It is not an official unit or recognized term in the International System of Units (SI).

Both scales use the same unit interval: one kelvin equals one degree Celsius in magnitude. The essential distinction is their zero points: 0 K corresponds to −273.15 °C. The conversion formulas are T(K) = T(°C) + 273.15 and T(°C) = T(K) − 273.15. Because of this, temperatures can be converted easily between scales, and many instruments display both.

In scientific practice, Kelvin is the preferred absolute temperature scale, used in thermodynamics and physics, while Celsius is common for everyday temperature and weather reporting. The Kelvin scale is the SI base unit for thermodynamic temperature, and since 2019 its definition is fixed by the Boltzmann constant rather than a physical artifact. Celsius remains defined by the same degree interval and offset relative to the Kelvin scale.

Historically, the Celsius scale was proposed by Anders Celsius in 1742, and the Kelvin scale was introduced by William Thomson, Lord Kelvin, in the mid-19th century. The term kelvincelsius may be encountered in discussions of conversion, data presentation, or educational materials, but it has no formal status in standard temperature nomenclature.