Square metre

The square metre (international spelling as used by the International Bureau of Weights and Measures) or square meter (American spelling) is the unit of area in the International System of Units (SI) with symbol m2. It is the area of a square with sides one metre in length.

Adding and subtracting SI prefixes creates multiples and submultiples; however, as the unit is exponentiated, the quantities grow exponentially by the corresponding power of 10. For example, 1 kilometre is 103 (one thousand) times the length of 1 metre, but 1 square kilometre is (103)2 (106, one million) times the area of 1 square metre, and 1 cubic kilometre is (103)3 (109, one billion) cubic metres.

Its inverse is the reciprocal square metre (m−2), often called "per square metre".

SI prefixes applied

The square metre may be used with all SI prefixes used with the metre.

Multiplication	Name	Symbol	Multiplication	Name	Symbol
100	**square metre** (centiare)	**m2**	100	**square metre** (centiare)	**m2**
102	square decametre (are)	dam2	10−2	square decimetre	dm2
103	kilo square metre	k(m2)	10−3	milli square metre	m(m2)
104	square hectometre (hectare)	hm2	10−4	square centimetre	cm2
106	square kilometre	km2	10−6	square millimetre	mm2
1012	square megametre	Mm2	10−12	square micrometre	μm2
1018	square gigametre	Gm2	10−18	square nanometre	nm2
1024	square terametre	Tm2	10−24	square picometre	pm2
1030	square petametre	Pm2	10−30	square femtometre	fm2
1036	square exametre	Em2	10−36	square attometre	am2
1042	square zettametre	Zm2	10−42	square zeptometre	zm2
1048	square yottametre	Ym2	10−48	square yoctometre	ym2
1054	square ronnametre	Rm2	10−54	square rontometre	rm2
1060	square quettametre	Qm2	10−60	square quectometre	qm2