In 1929, the international nautical mile was defined by the First International Extraordinary Hydrographic Conference in Monaco as precisely 1,852 meters. The United States nautical mile was defined as 6,080.20 feet (1,853.24 m) based in the Mendenhall Order foot of 1893. It was abandoned in favour of the international nautical mile in 1954. The Imperial nautical mile, often called an Admiralty mile, was defined by its relation to the Admiralty knot, and was abandoned in 1970.

1 mila morska ma 1852 metry, co odpowiada 40000 km / (360° × 60’). Niektóre państwa przyjmują nieco inne, zbliżone wartości (Wielka Brytania 1853,18 m; Holandia 1851,85 m; Portugalia 1850 m)

Auf der Erdoberfläche entspricht eine Winkelminute eines Erd-Großkreises etwa 1852 m. Daraus ist auch die Seemeile abgeleitet.