SI-Prefixes for Decimal Multiples
Prefix Abbreviation Decimal Factor Name
(American)
yotta Y
1,000,000,000,000,000,000,000,000
 1024 septillion
zetta Z
1,000,000,000,000,000,000,000
 1021 sextillion
exa E
1,000,000,000,000,000,000
 1018 quintillion
peta P
1,000,000,000,000,000
 1015 quadrillion
tera T
1,000,000,000,000
 1012 trillion
giga G
1,000,000,000
 109 billion
mega M
1,000,000
 106 million
kilo K
1,000
 103 thousand
hecto h
100
 102 hundred
deka da
10
 101 ten
   
1
 1 ones
deci d
0.1
 10-1 tenth
centi c
0.01
 10-2 hundredth
mili m
0.001
 10-3 thousandth
micro µ
0.000 001
 10-6 millionth
nano n
0.000 000 001
 10-9 billionth
pico p
0.000 000 000 001
 10-12 trillionth
femto f
0.000 000 000 000 001
 10-15 quadrillionth
atto a
0.000 000 000 000 000 001
 10-18 quintillionth
zepto z
0.000 000 000 000 000 000 001
 10-21 sextillionth
yocto y
0.000 000 000 000 000 000 000 001
 10-24 septillionth