SI Prefix Converter
Scale decimal orders of magnitude across all 25 official BIPM prefixes—from quetta (1030) down to quecto (10-30). Generic metric scaling for science, computing, and engineering.
Scaling Factor: 10^3 (1000)
🔬 How SI Prefix Scaling Works
Every SI prefix represents an exact power of 10. To convert any numeric quantity from prefix A with exponent eA to prefix B with exponent eB, multiply by:
Valuetarget = Valuesource × 10(esource − etarget)
Example: Converting 5 km to meters: exponent difference is 3 − 0 = +3. Hence 5 × 10³ = 5,000 m.
⚠️ Important Dimensional Rules
- Case Sensitivity: Capital
Mstands for mega (10⁶) while lowercasemstands for milli (10⁻³). Never confuse 1 MB with 1 mB. - Generic Scaling: SI prefixes are scaling multipliers, not independent physical units. A real conversion must apply to compatible dimensions (e.g. meters, grams, seconds).
- Micro Notation: The official symbol is Greek mu (µ), with standard plain ASCII alias
usupported in technical software.
Official BIPM SI Prefix Reference Table
Standardized by the International Bureau of Weights and Measures (BIPM).
| Prefix | Symbol | Power | Decimal Value | Real-World Example | Year |
|---|---|---|---|---|---|
| quetta | Q | 1030 | 1e+30 | 1 Qm = 10³⁰ m (observable universe scale) | 2022 |
| ronna | R | 1027 | 1e+27 | Mass of Earth ≈ 6 Rg (ronnagrams) | 2022 |
| yotta | Y | 1024 | 1e+24 | 1 YB = 10²⁴ bytes | 1991 |
| zetta | Z | 1021 | 1e+21 | Global digital data volume measured in zettabytes (ZB) | 1991 |
| exa | E | 1018 | 1e+18 | Exaflop supercomputers (10¹⁸ FLOP/s) | 1975 |
| peta | P | 1015 | 1e+15 | 1 PB = 10¹⁵ bytes | 1975 |
| tera | T | 1012 | 1e+12 | 1 TB hard drive = 10¹² bytes | 1960 |
| giga | G | 109 | 1e+9 | 1 GHz CPU clock = 10⁹ cycles/second | 1960 |
| mega | M | 106 | 1e+6 | 1 MW power plant = 10⁶ watts | 1960 |
| kilo | k | 103 | 1,000 | 1 km = 1,000 meters; 1 kg = 1,000 grams | 1795 |
| hecto | h | 102 | 100 | 1 hPa (hectopascal) = 100 pascals (barometric pressure) | 1795 |
| deca | da | 101 | 10 | 1 dal (decaliter) = 10 liters | 1795 |
| none | — | 100 | 1 | Base unit without prefix (10⁰ = 1) | 1960 |
| deci | d | 10-1 | 0.1 | 1 dm = 0.1 meter; 1 dL = 0.1 liter | 1795 |
| centi | c | 10-2 | 0.01 | 1 cm = 0.01 meter | 1795 |
| milli | m | 10-3 | 0.001 | 1 mm = 0.001 meter; 1 mL = 0.001 liter | 1795 |
| micro | µ | 10-6 | 1e-6 | 1 µm = 10⁻⁶ meter (micron; cell scale) | 1960 |
| nano | n | 10-9 | 1e-9 | 1 nm = 10⁻⁹ meter (visible light wavelength scale: ~400–700 nm) | 1960 |
| pico | p | 10-12 | 1e-12 | 1 pF (picofarad) = 10⁻¹² farad capacitor | 1960 |
| femto | f | 10-15 | 1e-15 | 1 fs (femtosecond) laser pulse = 10⁻¹⁵ s; proton radius ≈ 0.84 fm | 1964 |
| atto | a | 10-18 | 1e-18 | 1 as (attosecond) electron transition timescale | 1964 |
| zepto | z | 10-21 | 1e-21 | Elementary charge e ≈ 160 zC (zeptocoulombs) | 1991 |
| yocto | y | 10-24 | 1e-24 | Mass of proton ≈ 1.67 yg (yoctograms) | 1991 |
| ronto | r | 10-27 | 1e-27 | Mass of electron ≈ 0.91 rg (rontograms) | 2022 |
| quecto | q | 10-30 | 1e-30 | Mass of 1 bit in flash memory estimated in quectograms (qg) | 2022 |