kilogram, ampere, kelvin and mole set to be redefined

Source: Proposed redefinition of SI base units – Wikipedia

It is expected that the formal vote, scheduled for 16 November 2018, will be approved and that the new definitions will come into force on 20 May 2019.

There will still be the same seven base units (second, metre, kilogram, ampere, kelvin, mole, and candela). Of these, the kilogram, ampere, kelvin and mole will be redefined by choosing exact numerical values for the Planck constant, the elementary electric charge, the Boltzmann constant, and the Avogadro constant, respectively. The second, metre and candela are already defined by physical constants and it is only necessary to edit their present definitions.