Metric System (SI) Prefixes, also known as Metric prefixes or SI Prefixes, are useful to present a measurement unit in multiple or submultiple. The following table summarizes all commonly used prefixes.
| Prefix (Symbol) | Multiplication Factor (decimal multiple) | 10n | In Words | Exemple |
| yotta (Y) | 1,000,000,000,000,000,000,000,000 | 1024 | septillion | Yottameter (Ym) |
| zetta (Z) | 1,000,000,000,000,000,000,000 | 1021 | sextillion | Zettameter (Zm) |
| exa (E) | 1,000,000,000,000,000,000 | 1018 | quintillion | Exameter (Em) |
| peta (P) | 1,000,000,000,000,000 | 1015 | quadrillion | Petameter (Pm) |
| tera (T) | 1,000,000,000,000 | 1012 | trillion | Terameter (Tm) |
| giga (G) | 1,000,000,000 | 109 | billion | Gigameter (Gm) |
| mega (M) | 1,000,000 | 106 | million | Megameter (Mm) |
| kilo (k) | 1,000 | 103 | thousand | Kilometre (km) |
| hecto (h) | 100 | 102 | hundred | Hectometer (hm) |
| deca (da) | 10 | 101 | ten | Decameter (dam) |
| Base unit | 1 | 100 | one | Meter |
| deci (d) | 0.1 | 10-1 | tenth | Decimeter (dm) |
| centi (c) | 0.01 | 10-2 | hundredth | Centimeter (cm) |
| milli (m) | 0.001 | 10-3 | thousandth | Millimeter (mm) |
| micro (µ) | 0.000,001 | 10-6 | millionth | Micrometer (µm) |
| nano (n) | 0.000,000,001 | 10-9 | billionth | Nanometer (nm) |
| pico (p) | 0.000,000,000,001 | 10-12 | trillionth | Picometer (pm) |
| femto (f) | 0.000,000,000,000,001 | 10-15 | quadrillionth | Femtometer (fm) |
| atto (a) | 0.000,000,000,000,000,001 | 10-18 | quintillionth | Attometer (am) |
| zepto (z) | 0.000,000,000,000,000,000,001 | 10-21 | sextillionth | Zeptometer (zm) |
| yocto (y) | 0.000,000,000,000,000,000,000,001 | 10-24 | septillionth | Yoctometer (ym) |
