Free Unit Prefix Generator
From yocto to yotta, NToolHub’s Unit Prefix Generator makes metric prefixes effortless. Browse the complete SI prefix reference table — symbols, powers of ten, and real examples — and convert any value between prefixes instantly. Students, engineers, and science writers get exact conversions with scientific-notation output.
SI Prefix Reference Table
| Prefix | Symbol | Factor | Example |
|---|
How to Use the Unit Prefix Generator
- Enter a value and pick the “from” and “to” SI prefixes.
- Click “Convert” — results update live as you change inputs.
- Browse the full SI prefix reference table below, from yocto to yotta.
Features
All 21 SI prefixes from 10^-24 to 10^24 with symbols and examples, instant bidirectional conversion, scientific-notation display for extreme values, a base-unit equivalent shown for every conversion, and live updates on any input change.
Benefits & Use Cases
Prefix errors cause real disasters — unit conversion mistakes have downed spacecraft. This tool makes kilo-to-milli and giga-to-nano conversions foolproof for homework, lab work, and specs.
Tips
Remember that k is lowercase for kilo while M is uppercase for mega — case matters in SI. The base-unit value shown under each result is handy for formulas. For data sizes, note that computing sometimes uses binary prefixes instead.
Frequently Asked Questions
What is the full range of SI prefixes?
From yocto (10^-24) to yotta (10^24), covering 21 prefixes used across science and engineering.
Why is kilo lowercase but Mega uppercase?
SI convention: prefixes for 10^3 and below use lowercase (m, k), while 10^6 and above use uppercase (M, G), with a few historical exceptions.
Can I convert data sizes like MB to GB?
Yes for decimal SI units. Note that operating systems often use binary multiples, so results may differ slightly from what your OS reports.
How is the conversion calculated?
By the difference in exponents: converting 1 kilometre to metres multiplies by 10^(3-0), giving 1000.
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