Text Symbol Factor or
yotta Y 1024 1000000000000000000000000
zetta Z 1021 1000000000000000000000
exa E 1018 1000000000000000000
peta P 1015 1000000000000000
tera T 1012 1000000000000
giga G 109 1000000000
mega M 106 1000000
kilo k 103 1000
hecto h 102 100
deca da 101 10
(none) (none)  1
deci d 10−1 0.1
centi c 10−2 0.01
milli m 10−3 0.001
micro μ 10−6 0.000001
nano n 10−9 0.000000001
pico p 10−12 0.000000000001
femto f 10−15 0.000000000000001
atto a 10−18 0.000000000000000001
zepto z 10−21 0.000000000000000000001
yocto y 10−24 0.000000000000000000000001