Convert Furlong to Nautical Mile (fur → nmi)

Converting furlongs to nautical miles is straightforward: multiply by the conversion factor. Follow these three steps to do it by hand or in your head.

1. 1
   Take your value in furlongs

   Start with the number of furlongs (fur) you want to convert.
2. 2
   Multiply by 0.108622

   The conversion factor from fur to nmi is 0.108622. Multiply your value by this number.
3. 3
   Read the result in nautical miles

   The result is your value in nautical miles (nmi).

Multiply the value in furlongs by 0.108622. For the reverse direction, multiply by 9.206236.

• ✓1 furlong = 1/8 mile = 10 chains = 220 yards.
• ✓Convert quickly: 8 furlongs = 1 mile = 1.609 km.
• ✓Furlongs are used almost exclusively in horse racing — elsewhere they are largely historical.

• ✗Assuming furlongs appear in modern road distances — they do not.
• ✗Confusing furlongs with fathoms (a nautical depth unit).
• ✗Using 200 m as a shortcut when accuracy matters — the true value is 201.168 m.

What is the Furlong?

The furlong equals exactly 201.168 meters or one eighth of a mile (220 yards). The unit's name comes from the Old English 'furh' (furrow) and 'lang' (long), reflecting its origin as the length of a furrow that an ox team could plow without resting. Formalized in medieval England, the furlong was standardized as 40 rods or 660 feet during agricultural land measurement. Today, the furlong's primary modern use is in horse racing across the United Kingdom, the United States, and several Commonwealth countries — race distances are quoted in furlongs (a 6-furlong sprint is ¾ of a mile). It also appears in old land deeds, particularly in Britain. The furlong relates to the mile (8 furlongs = 1 mile), the yard (220 yd = 1 furlong), and the meter (≈201 m).

• Flat racing and National Hunt distances in the UK
• Thoroughbred racing in the US and Canada
• Historical land measurement in England

What is the Nautical Mile?

The nautical mile equals exactly 1,852 meters and is the international standard distance unit for marine navigation, aviation, and polar geography. It was originally defined as one minute of arc along a meridian — meaning 60 nautical miles equal one degree of latitude. This relationship makes the nautical mile uniquely useful for charts: a navigator can read distance directly off the latitude scale of any map. Adopted internationally in 1929, the nautical mile is used by virtually all maritime nations and in international aviation regulations. The related speed unit is the knot (1 nautical mile per hour). The nautical mile is roughly 1.151 statute miles or 1.852 km. Distinct from the older British nautical mile (6,080 ft) and the US nautical mile (6,080.20 ft), the international nautical mile is now standard worldwide.

• Marine navigation and nautical charts
• Commercial and military aviation distances
• International maritime law (territorial waters = 12 nmi)