## kelvin, $$\text{K}$$

https://doi.org/10.1351/goldbook.K03374
The kelvin, symbol $$\text{K}$$, is the SI unit of thermodynamic temperature. It is defined by taking the fixed numerical value of the Boltzmann constant k to be 1.380 649 x 10E-23 when expressed in the unit J K-1, which is equal to kg m2 s-2 K-1, where the kilogram, metre and second are defined in terms of h, c and ΔνCs.
Source:
BIPM, The International System of Units, SI Brochure, 9th ed. (2019) (http://www.bipm.org/en/publications/si-brochure/)