The International System of Units (SI) is based on nine physical quantities.

Physical Quantity	Unit name	Unit Symbol
Length	metre	m
Mass	kilogram	kg
Time	second	s
Plane Angle	radian	rad
Amount of substance	mole	mol
Electric current	ampere	A
Luminous intensity	candela	cd
Solid angle	steradian	sr
Thermodynamic temperature	kelvin	K