Bridget from North Dakota contacted me on April 23, 2006, asking why I do not include the prefixes deca, deci and centi in my conversion tools. Finally I decided to add the following chart to the site; I found it elsewhere on the Internet a couple of years ago and simply cleaned up the page code.

The most commonly used prefixes are in the middle portion of the table. On most browsers these will appear in black-and-white, and the others will appear in maroon against a green background.

    Multiplier
Prefix Symbol Numerical Exponential
yotta Y 1,000,000,000,000,000,000,000,000 1024
zetta Z 1,000,000,000,000,000,000,000 1021
exa E 1,000,000,000,000,000,000 1018
peta P 1,000,000,000,000,000 1015
tera T 1,000,000,000,000 1012
giga G 1,000,000,000 109
mega M 1,000,000 106
kilo k 1,000 103
hecto h 100 102
deka da 10 101
no prefix 1 100
deci d 0.1 10-1
centi c 0.01 10-2
milli m 0.001 10-3
micro µ 0.000001 10-6
nano n 0.000000001 10-9
pico p 0.000000000001 10-12
femto f 0.000000000000001 10-15
atto a 0.000000000000000001 10-18
zepto z 0.000000000000000000001 10-21
yocto y 0.000000000000000000000001 10-24

A Few Notes

More on Metric Prefixes