Multiples and Submultiples of SI Units
A reference table showing the SI unit prefixes, symbols and multiplication factors used in the International System of Units (SI).
| Prefix | Symbol | Multiplying Factor |
|---|---|---|
| exa | E | 1018 1 000 000 000 000 000 000 |
| peta | P | 1015 1 000 000 000 000 000 |
| tera | T | 1012 1 000 000 000 000 |
| giga | G | 109 1 000 000 000 |
| mega | M | 106 1 000 000 |
| kilo | k | 103 1 000 |
| hecto* | h | 102 100 |
| deca* | da | 101 10 |
| deci* | d | 10-1 0.1 |
| centi | c | 10-2 0.01 |
| milli | m | 10-3 0.001 |
| micro | µ | 10-6 0.000 001 |
| nano | n | 10-9 0.000 000 001 |
| pico | p | 10-12 0.000 000 000 001 |
| femto | f | 10-15 0.000 000 000 000 001 |
| atto | a | 10-18 0.000 000 000 000 000 001 |
* Note: These prefixes are not normally used.