A per mil or per mille (also spelled permil, permille^{[1]}, per mill or promille) (Latin, literally meaning 'for (every) thousand') is a tenth of a percent or one part per thousand. It is written with the sign ‰ (Unicode U+2030)., which looks like a percent sign (%) with an extra zero at the end. It can be seen as a stylized form of the three zeros in the denominator, although it originates from an alteration of the percent sign.
A per mil is defined as:
A per mil should not be confused with ppm (commonly pronounced "parts per mil" in the United States). A measurement in ppm means parts per million, and has as its denominator 1,000,000 and not 1,000.
Examples of common use are:
