About this tool
Metric Prefix Converter takes a value written with one SI metric prefix and shows it in every other prefix, so you can answer the conversions that come up constantly in physics, chemistry, electronics, and engineering: convert kilo to mega, milli to micro, nano to pico, GHz to MHz, kilohms to ohms, or microfarads to nanofarads. It works two ways. In Smart input you type a number with a prefix and unit exactly as you would read it, such as 4.7 kohm, 2200 uF, 1.5 GHz, 330 nF, or 5 mm; the tool detects the prefix, keeps the unit only for display, and lists the same quantity expressed in quetta down to quecto, the full set of twenty four SI prefixes including the ronna, quetta, ronto, and quecto prefixes the General Conference on Weights and Measures added in 2022. In From and to prefix mode you enter a plain number, pick a source prefix and a target prefix from dropdowns, and read the single converted value plus a complete table; a swap button flips the two prefixes. Because metric prefixes span sixty orders of magnitude, naive floating point math drifts and starts printing values in unexpected exponent form, so this tool keeps each value as an exact base ten figure made of its significant digits and a power of ten, shifts the power when it changes prefix, and only falls back to scientific notation when the plain decimal would be too long to read. Alongside the prefix table it always shows the value in scientific (E) notation and in engineering notation, where the exponent is a multiple of three, which is how component values and measurements are usually quoted. Micro is the prefix people most often cannot type, so the tool accepts u, mc, the micro sign, and the Greek mu and treats them all as micro, and it accepts an uppercase K for kilo as a convenience even though the correct symbol is a lowercase k. It is careful with single letters: a lone m or g is read as a unit, metre or gram, rather than as the milli prefix, so 5 m stays five metres. This converter is different from a scientific notation converter, which only moves between times ten to the power forms, and from a data size converter, which handles bytes such as KB, MB, and GB; this one works with any quantity and converts directly from one prefix to another. Every prefix in the result can be copied on its own, or you can copy the whole table at once. Nothing you type is uploaded; all of the math runs in your browser.
Free to use. Works in your browser. No signup, no login.