The kelvin, symbol \(\text{K}\), is the SI unit of thermodynamic temperature. It is defined by taking the fixed numerical value of the @B00695@ \(k\) to be \(1.380\ 649\times 10^{-23}\) when expressed in the unit \(\text{J K}^{-1}\), which is equal to \(\text{kg}\ \text{m}^{2}\ \text{s}^{-2}\ \text{K}^{-1}\), where the kilogram, metre and second are defined in terms of @P04685@, @S05854-1@ and @S05854-2@.
BIPM, The International System of Units, SI Brochure, 9th ed. (2019), p. 133 [Terms] [Book]