| Name | Letter | Description | Suffix | Number |
|---|---|---|---|---|
| yocto | y | septillionth | 10-24 | .000 000 000 000 000 000 000 001 |
| zepto | z | sextillionth | 10-21 | .000 000 000 000 000 000 001 |
| atto | a | quintillionth | 10-18 | .000 000 000 000 000 001 |
| femto | f | quadrillionth | 10-15 | .000 000 000 000 001 |
| pico | p | trillionth | 10-12 | .000 000 000 001 |
| angtrom# | Å | ten billionth | 10-10 | .000 000 000 000 1 |
| #Used by physicists, and materials Scientist's. Engineers use nanometres to describe small IC features as we use powers in steps of 3. | ||||
| nano | n | billionth | 10-9 | .000 000 001 |
| micro | µ | millionth | 10-6 | .000 001 |
| milli | m | thousandth | 10-3 | .001 |
| centi | c | hundredth | 10-2 | .01 |
| deci | d | tenth | 10-1 | .1 |
| deca | da | ten | 101 | 10 |
| hecto | h | hundred | 102 | 100 |
| kilo | k | thousand | 103 | 1 000 |
| mega | M | million | 106 | 1 000 000 |
| giga | G | billion | 109 | 1 000 000 000 |
| tera | T | trilion | 1012 | 1 000 000 000 000 |
| peta | P | quadrillion | 1015 | 1 000 000 000 000 000 |
| exa | E | quintillion | 1018 | 1 000 000 000 000 000 000 |
| zetta | Z | sextillion | 1021 | 1 000 000 000 000 000 000 000 |
| yotta | Y | septillion | 1024 | 1 000 000 000 000 000 000 000 000 |
| tebi | 1040 | |||
| googol | 10100 |
Note: the google search engine is based on this number but uses a different spelling. |
||
| googolplex* | 10googol | |||
*Probably higher than the number of Atoms in the known Universe of 100 Billion known Galaxies each with 400 Billion or so Stars.