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kilogram

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The kilogram is the unit of mass; it is equal to the mass of the international prototype of the kilogram.

This definition is valid from 1901-05-20 to 2019-05-19
Unit kilogram
Symbol kg
Quantity mass
Unit Type SI base unit
Notes:
  1. This international prototype, made of platinum-iridium, is kept at the BIPM under conditions specified by the 1st CGPM in 1889.
www.bipm.org