International System of Units

SI Base Units

Base quantity	Name	Symbol
lenght	metre	m
mass	kilogram	kg
time	second	s
electric current	ampere	A
thermodynamic temperature	kelvin	K
amount of substance	mole	mol
luminous intensity	candela	cd

SI prefixes

Name	Symbol	Factor	Name	Symbol	Factor
exa	E	1018	deci	d	10−1
peta	P	1015	centi	c	10−2
tera	T	1012	milli	m	10−3
giga	G	109	micro	μ	10−9
mega	M	106	nano	n	10−9
kilo	k	103	pico	p	10−12
hecto	h	102	femto	f	10−15
deka	da	101	atto	a	10−18

SI derived units

Derived quantity	Name	Symbol	Definition
area	square metre		m2
volume	cubic metre		m3
speed, velocity	metre per second		m/s
acceleration	metre per second squared		m/s2
frequency	hertz	Hz	1/s
plane angle	radian	rad
solid angle	steradian	sr
force	newton	N	kg ∙ m/s2
pressure	pascal	Pa	N/m2
energy, work, quantity of heat	joule	J	N ∙ m
power	watt	W	J/s
electric charge	coulomb	C	s ∙ A
electric potential difference	volt	V	W/A
capacitance	farad	F	C/V
electric resistance	ohm	Ω	V/A
magnetic flux	weber	Wb	V ∙ s
magnetic flux density	tesla	T	Wb/m2