Kortnie is of American origin, derived from the English name Courtney. It gained popularity during the late 20th century as a unique and modern alternative to traditional names like Courtney or Kortney. The name Kortnie typically has one 't', unlike its variants, which can sometimes have two. In many cases, Kortnie is used as a middle name rather than a first name, adding a touch of uniqueness without being too unusual for everyday use. Its popularity peaked in the late 1980s and early 1990s but has since declined somewhat, making it now less common than it once was.
The name Kortnie experienced significant popularity between the late 1980s and mid-1990s, peaking with 58 births in 1993, but has since declined to fewer than 10 births per year since 2007.