Understanding SI prefixes

A practical guide to kilo, mega, giga, milli, micro and scientific notation.

Decimal prefixes are powers of ten: kilo is 10³, mega is 10⁶, milli is 10⁻³ and micro is 10⁻⁶. Binary prefixes such as kibi (2¹⁰) and mebi (2²⁰) are different and are commonly used for digital storage. Always check whether a product or standard uses decimal or binary units.

Important note

The calculation is performed locally from the listed unit definitions. Display results are rounded for readability; high-precision and regulated work should use the governing standard and appropriate significant figures.

Related conversions: Length, Mass & weight, Temperature, Digital storage, Energy, Power.

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