Metric prefixes
These are the commonly used SI metric multiplier prefixes…
Unit |
Abbreviation |
Factor (power of ten) |
Factor (number) |
Quetto |
q |
1.E-30 |
0.000000000000000000000000000001 |
Ronno |
r |
1.E-27 |
0.000000000000000000000000001 |
Yotto |
y |
1.E-24 |
0.000000000000000000000001 |
Zepto |
z |
1.E-21 |
0.000000000000000000001 |
Atto |
a |
1.E-18 |
0.000000000000000001 |
Femto |
f |
1.E-15 |
0.000000000000001 |
Pico |
p |
1.E-12 |
0.000000000001 |
Nano |
n |
1.E-09 |
0.000000001 |
Micro |
µ |
1.E-06 |
0.000001 |
Milli |
m |
1.E-03 |
0.001 |
Centi |
c |
1.E-02 |
0.01 |
Deci |
d |
1.E-01 |
0.1 |
(none) |
0 |
1 |
|
Deca |
da |
1.E+01 |
10 |
Hecto |
h |
1.E+02 |
100 |
Kilo |
k |
1.E+03 |
1,000 |
Myria |
(rare) |
1.E+04 |
10,000 |
Mega |
M |
1.E+06 |
1,000,000 |
Giga |
G |
1.E+09 |
1,000,000,000 |
Tera |
T |
1.E+12 |
1,000,000,000,000 |
Peta |
P |
1.E+15 |
1,000,000,000,000,000 |
Exa |
E |
1.E+18 |
1,000,000,000,000,000,000 |
Zetta |
Z |
1.E+21 |
1,000,000,000,000,000,000,000 |
Yotta |
Y |
1.E+24 |
1,000,000,000,000,000,000,000,000 |
Ronna |
R |
1.E+27 |
1,000,000,000,000,000,000,000,000,000 |
Quetta |
Q |
1.E+30 |
1,000,000,000,000,000,000,000,000,000,000 |
Updated 2022-11-29 to take into account the new metric prefixes agreed at General Conference on Weights and Measures (CGPM) 2022. More info.