base units
Metric system standards
Base units are the fundamental units of measurement from which all other units in a system are derived.
In the International System (SI), there are seven: the meter (length), kilogram (mass), second (time), ampere (electric current), kelvin (temperature), mole (amount of substance), and candela (luminous intensity).
All other SI units—newtons, joules, watts—are built from combinations of these.
- kilogramBase unit of mass
- metric tonThousand-kilogram mass unit
- secondUnit smaller than minute
- atomic clockQuantum-vibration timekeeping device
- meterDevice that measures usage
measuring stick · light year · ampere · length · candela · measurement · metric system · decimal system · reference standards · mole · SI units · traceability · mass · quantity · time · metrology · electric current · fundamental