Nautical mile

Unit symbol

There is no single internationally agreed symbol.^[1]

• M is used as the abbreviation for the nautical mile by the International Hydrographic Organization^[4] and by the International Bureau of Weights and Measures.^[1]
• NM is used by the International Civil Aviation Organization.^[5][6]
• nm (the SI symbol for the nanometre) is used by the U.S. National Oceanic and Atmospheric Administration.^[7]
• nmi is used by the Institute of Electrical and Electronics Engineers^[8] and the United States Government Publishing Office.^[9]
• nq (from the French word nautique) is used by the French Navy in the ship's logs.

While using M itself, the International Bureau of Weights and Measures recognises that NM, Nm and nmi are also in use.^[1]