⚓ Nautical Mile Calculator
Convert NM to km, miles, feet & yards. Calculate speed in knots, travel time, and latitude distances. 🌊
Nautical Mile Unit Converter
Type in any field — all others update instantly
Knots Speed Converter
1 knot = 1 NM/h = 1.852 km/h — type in any field
🧭 Navigation Calculator
Solve the navigation triangle: Distance = Speed × Time
Latitude to Nautical Miles
1° latitude = 60 NM · 1′ (arcminute) = 1 NM
| Degrees of Latitude | Nautical Miles | Kilometers |
|---|---|---|
| 0.5° (30′) | 30 NM | 55.56 km |
| 1° (60′) | 60 NM | 111.12 km |
| 5° | 300 NM | 555.6 km |
| 10° | 600 NM | 1,111.2 km |
| 45° | 2,700 NM | 5,004 km |
| 90° (pole) | 5,400 NM | 10,008 km |
| 360° (full) | 21,600 NM | 40,003 km |
Nautical Mile Conversion Table
Reference| Nautical Miles | Kilometers | Statute Miles | Meters | Feet |
|---|---|---|---|---|
| 1 NM | 1.852 | 1.15078 | 1,852 | 6,076.12 |
| 5 NM | 9.26 | 5.754 | 9,260 | 30,380.6 |
| 10 NM | 18.52 | 11.508 | 18,520 | 60,761.2 |
| 50 NM | 92.6 | 57.539 | 92,600 | 303,806 |
| 100 NM | 185.2 | 115.078 | 185,200 | 607,612 |
| 500 NM | 926 | 575.39 | 926,000 | 3,038,060 |
| 1,000 NM | 1,852 | 1,150.78 | 1,852,000 | 6,076,120 |
⚓ What is a Nautical Mile?
A nautical mile (NM) is a unit of distance used exclusively in air and sea navigation. It is defined as exactly 1,852 metres (approximately 1.151 statute miles or 6,076 feet). Unlike the statute mile, the nautical mile has a direct relationship with Earth's geometry — it is equal to 1 minute (1′) of arc of latitude along any meridian.
The definition emerges from the fact that the Earth's circumference measured through the poles is approximately 40,003 km. Dividing this by 360 degrees and again by 60 arcminutes yields ≈ 1,852 m — a distance that lets navigators read distance directly from a latitude scale on any chart.
The term "nautical mile" dates to the 17th century, but its modern definition was internationally standardized in 1929 at the International Extraordinary Hydrographic Conference in Monaco. It was adopted by the International Hydrographic Organization and subsequently by the ICAO for aviation and IMO for maritime use.
Why is a Nautical Mile Different from a Regular Mile?
- • Exactly 1,609.344 metres
- • Historically: 8 furlongs = 5,280 feet
- • Used on US & UK roads
- • No direct link to Earth's geometry
- • Exactly 1,852 metres
- • = 1 arcminute of latitude
- • Used in aviation & maritime worldwide
- • Chart coordinates = distances directly
🌊 Knots Explained
A knot (kn or kt) is the unit of speed used by ships and aircraft. 1 knot = 1 nautical mile per hour = 1.852 km/h = 1.15078 mph = 0.51444 m/s. Because distances at sea are measured in nautical miles, using knots keeps speed and distance in the same unit system — making time calculations straightforward.
The word "knot" comes from an old method of measuring ship speed: a piece of wood (the chip log) was thrown overboard, and sailors counted how many knots in a rope paid out over a 28-second sandglass as the rope ran free. The number of knots that slipped through a sailor's hands was the ship's speed in knots.
Typical operational speeds
⚓ Famous Nautical Distances
| Route | Nautical Miles | Kilometers |
|---|---|---|
| 🌍 Earth's equatorial circumference | 21,639 NM | 40,075 km |
| 🌊 London → New York (Atlantic) | 2,985 NM | 5,530 km |
| ⚓ Sydney → Los Angeles (Pacific) | 6,504 NM | 12,048 km |
| 🗺️ Cape Town → Mumbai (Indian Ocean) | 4,662 NM | 8,634 km |
| 🌊 Panama Canal (Pacific to Atlantic) | 44 NM | 82 km |
| ⚓ English Channel width (narrowest) | 18 NM | 33 km |
| ✈️ Dubai → Singapore (air route) | 3,236 NM | 5,992 km |
Frequently Asked Questions
What is a nautical mile?
A nautical mile (NM) is a unit of length used in air and sea navigation equal to exactly 1,852 meters (about 1.151 statute miles). It is based on the Earth's circumference: 1 NM equals 1 minute of arc of latitude along any meridian — this makes it ideal for navigation since latitude and longitude degrees and minutes on a chart directly correspond to distances.
Why is a nautical mile different from a regular mile?
A statute mile is exactly 1,609.344 meters, defined historically from Roman and English measurements (5,280 feet). A nautical mile is 1,852 meters, derived from Earth's geometry. The nautical mile is ~15% longer than a statute mile. Navigators prefer nautical miles because the distance between two points can be read directly from latitude lines on any nautical chart — 1 NM per arcminute of latitude.
What is a knot in speed?
A knot is a unit of speed equal to one nautical mile per hour. It equals 1.852 km/h, approximately 1.151 mph, or 0.514 m/s. The name comes from the historical practice of using a knotted rope to measure a ship's speed. Knots are the international standard for maritime and aviation speeds, used universally in meteorology for wind speeds and in all commercial and military aviation.
How do I convert nautical miles to kilometers?
To convert nautical miles to kilometers, multiply by 1.852. For example, 10 NM × 1.852 = 18.52 km. To convert kilometers back to nautical miles, divide by 1.852 (or multiply by 0.53996). The factor 1.852 is exact by the international definition of the nautical mile.
How far is 1 degree of latitude in nautical miles?
One degree of latitude equals exactly 60 nautical miles. This is because 1 degree of latitude = 60 arcminutes, and by definition 1 NM = 1 arcminute of latitude. So 1° = 60 NM = 111.12 km. This relationship makes the nautical mile one of the most practical distance units for navigation — you can read distance directly from the latitude scale on any nautical chart.