Scientific Notation Calculator

Convert numbers to scientific notation and engineering notation. Control significant figures and see coefficient and exponent.

This tool expresses a number two different ways at once: ordinary scientific notation, where the exponent can be any integer, and engineering notation, where the exponent is forced to a multiple of three so it lines up with SI prefixes like kilo, mega, and giga. Both share the same underlying exponent, found by taking the base-ten logarithm of the number's magnitude and rounding down, then dividing the number by ten raised to that power to get the coefficient. The engineering exponent is derived from the scientific one by rounding down to the nearest multiple of three, which is why the default value of 123,456.789 — scientific exponent 5 — reports an engineering exponent of 3 alongside a correspondingly larger coefficient. Significant Figures controls how many digits the coefficient keeps in both notations, and while the input field on the page only exposes values from 1 to 15, the underlying calculation will accept anything from 1 up to 100 if driven with a higher value directly — the on-page stepper is narrower than what the formula itself supports. Superscript digits for the exponent are built character by character from a small lookup table, which is why the exponent renders as a raised character rather than a caret-and-number pairing. One thing this page will not produce is a plain standard-form rendering with the number written out in full; the dedicated Standard Form Calculator elsewhere on this site covers that, using a different, loop-based method rather than a logarithm to find its exponent.