This is a list of the names of small decimal numbers in English.
The following table lists the names of small numbers used in the long and short scales, along with the power of 10, engineering notation, and International System of Units (SI) symbols and prefixes.[1] [2] [3] [4] [5] [6] [7]
| Power of ten | Engineering notation | Short scale (U.S. and modern British) | Long scale (continental Europe, archaic British, and India) | SI prefix | SI symbol | |
|---|---|---|---|---|---|---|
| 100 | 1 | |||||
| 10−1 | 100×10−3 | One Tenth | deci- | d | ||
| 10−2 | 10×10−3 | centi- | c | |||
| 10−3 | 1×10−3 | milli- | m | |||
| 10−6 | 1×10−6 | micro- | μ | |||
| 10−9 | 1×10−9 | One One-Billionth | One One-Milliardth | nano- | n | |
| 10−12 | 1×10−12 | One One-Trillionth | One One-Billionth | pico- | p | |
| 10−15 | 1×10−15 | One One-Quadrillionth | One One-Billiardth | femto- | f | |
| 10−18 | 1×10−18 | One One-Quintillionth | One One-Trillionth | atto- | a | |
| 10−21 | 1×10−21 | One One-Sextillionth | One One-Trilliardth | zepto- | z | |
| 10−24 | 1×10−24 | One One-Septillionth | One One-Quadrillionth | yocto- | y | |
| 10−27 | 1×10−27 | One One-Octillionth | One One-Quardilliardth | r | ||
| 10−30 | 1×10−30 | One One-Nonillionth | One One-Quintillionth | quecto- | q | |
| 10−33 | 1×10−33 | One One-Decillionth | One One-Quintilliardth | |||
| 10−36 | 1×10−36 | One One-Undecillionth | One One-Sextillionth | |||
| 0 | 1×10−∞ | Zero | ||||
| –1 | –1 | Negative One | ||||
| −∞ | undefined | Negative Infinity | ||||