Si Unit Converter
Free online metric prefixes unit converter.
Convert between all metric prefixes units instantly with accurate results, formulas, and reference tables.
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Frequently Asked Questions
Common questions about the Si Unit Converter
SI prefixes indicate powers of 10, from yocto (10⁻²⁴) to yotta (10²⁴). Common ones include milli (10⁻³), kilo (10³), mega (10⁶), and giga (10⁹).
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Sources & References
SI prefixes (kilo, mega, milli, …)
Standard decimal prefixes for the International System of Units, from quecto (10⁻³⁰) to quetta (10³⁰), as defined by the BIPM and published by NIST.
International System of Units (SI)
Authoritative definitions for SI prefix definitions, from the BIPM SI Brochure (9th edition), the defining reference for the SI.