Metric Prefixes Converter
Convert between SI metric prefixes from yocto to yotta or Base Converter.
SI Prefix Reference Table
| Prefix | Symbol | Factor | Power |
|---|---|---|---|
| yotta | Y | 1000000000000000000000000 | 10^24 |
| zetta | Z | 1000000000000000000000 | 10^21 |
| exa | E | 1000000000000000000 | 10^18 |
| peta | P | 1000000000000000 | 10^15 |
| tera | T | 1000000000000 | 10^12 |
| giga | G | 1000000000 | 10^9 |
| mega | M | 1000000 | 10^6 |
| kilo | k | 1000 | 10^3 |
| hecto | h | 100 | 10^2 |
| deka | da | 10 | 10^1 |
| deci | d | 0.1 | 10^-1 |
| centi | c | 0.01 | 10^-2 |
| milli | m | 0.001 | 10^-3 |
| micro | µ | 0.000001 | 10^-6 |
| nano | n | 0.000000001 | 10^-9 |
| pico | p | 0.000000000001 | 10^-12 |
| femto | f | 0.000000000000001 | 10^-15 |
| atto | a | 0.000000000000000001 | 10^-18 |
| zepto | z | 0.000000000000000000001 | 10^-21 |
| yocto | y | 0.000000000000000000000001 | 10^-24 |
How SI Metric Prefix Conversion Works
The International System of Units (SI) defines 20 metric prefixes that scale a base unit by powers of 10, ranging from yocto (10⁻²⁴) to yotta (10²⁴). To convert between prefixes, you calculate the difference in their powers of 10 and shift the value accordingly. For example, converting from kilo (10³) to milli (10⁻³) means shifting by 10⁶ — so 1 kilometer = 1,000,000 millimeters. These prefixes work with any SI unit: meters, grams, liters, watts, hertz, and more.
Metric Prefix Conversion Formula
Result = Value × 10^(source_power − target_power). Equivalently: convert the value to the base unit first (multiply by 10^source_power), then convert from the base unit to the target prefix (divide by 10^target_power). For example, to convert 5 kilometers to centimeters: 5 × 10^(3−(−2)) = 5 × 10⁵ = 500,000 centimeters.
Worked Example: Convert 2.5 Megabytes to Kilobytes
Mega = 10⁶, Kilo = 10³. Power difference = 6 − 3 = 3. Result = 2.5 × 10³ = 2,500 kilobytes. Another example: Convert 750 nanometers to micrometers. Nano = 10⁻⁹, Micro = 10⁻⁶. Power difference = −9 − (−6) = −3. Result = 750 × 10⁻³ = 0.75 micrometers. This is the wavelength of red light, commonly expressed as either 750 nm or 0.75 µm.
Practical Applications of Metric Prefixes
Everyday life: kilo (kg, km, kW), centi (cm), milli (mL, mm, mg). Computing: giga (GB, GHz), tera (TB), mega (MB, MHz), kilo (KB). Science: nano (nm for light wavelengths, nanoparticles), micro (µm for cells, µs for timing), pico (pF for capacitors, ps for laser pulses). Engineering: mega (MPa for pressure), giga (GW for power plants). Telecommunications: tera (Tbps for fiber optic bandwidth), giga (Gbps for network speeds). Medicine: micro (µg for drug dosages), nano (nm for imaging resolution).
Technical Details
The SI prefix system was established by the General Conference on Weights and Measures (CGPM). The most recent additions were ronna (10²⁷), quetta (10³⁰), ronto (10⁻²⁷), and quecto (10⁻³⁰) in 2022, though this tool covers the traditional 20 prefixes from yocto to yotta. Note that in computing, binary prefixes (kibi, mebi, gibi) defined by IEC 80000-13 use powers of 1024 instead of 1000 — 1 kibibyte (KiB) = 1024 bytes, while 1 kilobyte (kB) = 1000 bytes in strict SI usage. This converter uses strict SI (powers of 10) for all calculations.
Frequently Asked Questions
How many millimeters are in a kilometer? 1 km = 10⁶ mm = 1,000,000 mm. The power difference is 3 − (−3) = 6. What is the difference between mega and giga? Mega is 10⁶ (million) and giga is 10⁹ (billion). 1 gigabyte = 1,000 megabytes in SI terms. Why are there 20 SI prefixes? The prefixes cover a range of 10⁴⁸ (from 10⁻²⁴ to 10²⁴), which spans the scales needed in science — from subatomic particles to astronomical distances. Is "micro" the same as the µ symbol? Yes, the prefix micro is represented by the Greek letter mu (µ). In computing contexts where µ is unavailable, "u" is sometimes used as a substitute (e.g., "uF" for microfarads). What is the smallest SI prefix? Yocto (y) at 10⁻²⁴. One yoctogram is approximately the mass of a single proton.