The kilogram (symbol kg) is the SI base unit of mass, per the BIPM SI Reference Point.
- Name: kilogram
- Symbol: kg
- Unit type: SI base unit
- Quantity kind: mass
- Definition (status current, in force since 2019-05-20): The kilogram, symbol $\rm{kg}$, is the SI unit of mass. It is defined by taking the fixed numerical value of the Planck constant, ${h}$, to be $6.626\:070\:15 \times 10^{-34}$ when expressed in the unit ${\rm{J}}\ {\rm{s}}$, which is equal to ${\rm{kg}}\ {\rm{m}}^{2}\ {\rm{s}}^{-1}$, where the metre and the second are defined in terms of $c$ and $\Delta\nu_{\rm{Cs}}$.
- Defining constant: Planck constant (fixed numerical value 6.626 070 15 x 10⁻³⁴)
- Defining equation: 1\;{\rm{kg}} = \left(\frac{{h}}{6.626\:070\:15 \times 10^{-34}}\right) {\rm{m}}^{-2}\;{\rm{s}}
- Defining resolution: https://si-digital-framework.org/bodies/CGPM#CGPM26-Res1
- Superseded definitions: kilogram1901 (1901-05-20 to 2019-05-19)
- Prefixed unit: kilo + gram