Convert Mile to Nautical Mile
Convert miles to nautical miles instantly. 1 mile = 0.8689762419 nautical mile — use the live calculator, the exact formula, a conversion table and worked examples. Also check the Nautical Mile to Mile converter for the reverse conversion.
Units explained
Mile
A mile (statute mile) is an Imperial and US customary unit of length equal to 5,280 feet or exactly 1,609.344 meters. It is the standard unit for road distances in the United States and the United Kingdom.
The mile derives from the Roman mille passus ("thousand paces" — about 1,480 meters). The English statute mile was fixed at 5,280 feet by the Weights and Measures Act of 1593, and exactly defined as 1,609.344 m by the 1959 International Yard and Pound Agreement.
Miles are used in the US and UK for road signs, speed limits (mph), athletic events (one-mile run), and geographic distances. Aviation also uses statute miles for some visibility measurements.
Roman origin (mille passus); English statute mile fixed at 5,280 feet in 1593; standardized to 1,609.344 m exactly by the 1959 International Yard and Pound Agreement.
Nautical Mile
A nautical mile is a unit of length equal to exactly 1,852 meters, defined as one minute of arc along any meridian of the Earth. It is the standard unit for sea and air navigation worldwide.
Originally defined as one minute of arc along a great circle of the Earth, making it convenient for celestial navigation. The International Hydrographic Organization (IHO) standardized the value at exactly 1,852 meters in 1929.
Nautical miles are used in maritime navigation, aviation, and international law (territorial waters, exclusive economic zones). Speed in nautical miles per hour is called a knot. The nautical mile is distinct from the statute (land) mile.
Defined for celestial navigation since antiquity; standardized to 1,852 m exactly by the IHO in 1929; adopted by the International Civil Aviation Organization (ICAO) for aviation use.
Mile to Nautical Mile conversion formula
The relationship between miles and nautical miles:
To convert miles to nautical miles, multiply the value in miles by 0.8689762419. To reverse, multiply nautical miles by 1.150779448.
How to use this converter
Type a value into the calculator. The result in nautical miles updates as you type. Tap a quick value, copy the result with one click, or use the swap arrow to jump straight to the Nautical Mile to Mile converter for the reverse direction.
Step-by-step: convert miles to nautical miles
- Write down the value in miles (mi).
- Multiply that value by the factor 0.8689762419.
- The product is the equivalent value in nautical miles (nmi).
- To reverse, multiply the nautical mile value by 1.150779448.
Worked examples
Example 1 — Convert 1 mi to nmi:
1 × 0.8689762419 = 0.8689762419 nmi
Example 2 — Convert 100 mi to nmi:
100 × 0.8689762419 = 86.8976241901 nmi
Real-world example — Endurance race distances
A 50-mile cycling or running race converts to a recognizable distance in nautical miles. Endurance athletes coming from a different measurement system use this conversion to compare training plans across regions.
50 mi × 0.8689762419 = 43.448812095 nmi
Real-world example — Maritime exclusion zone
A 200-mile exclusion zone (a common maritime boundary) converts to a different value in nautical miles that's useful when describing the same zone in everyday land-distance units.
200 mi × 0.8689762419 = 173.7952483801 nmi
Real-world example — Coastal cruise distances
A 10-mile coastal sailing route converts to a different value in nautical miles — useful for cruise operators who switch between maritime, aviation, and road-distance units depending on the leg of the trip.
10 mi × 0.8689762419 = 8.689762419 nmi
Mile to Nautical Mile conversion table
Standard reference values for converting miles to nautical miles:
| Mile [mi] | Nautical Mile [nmi] |
|---|---|
| 0.01 | 0.0086897624 |
| 0.1 | 0.0868976242 |
| 1 | 0.8689762419 |
| 2 | 1.7379524838 |
| 3 | 2.6069287257 |
| 4 | 3.4759049676 |
| 5 | 4.3448812095 |
| 10 | 8.689762419 |
| 20 | 17.379524838 |
| 30 | 26.069287257 |
| 40 | 34.759049676 |
| 50 | 43.448812095 |
| 100 | 86.8976241901 |
| 500 | 434.4881209503 |
| 1000 | 868.9762419006 |
Frequently asked questions
How many nautical miles is 1 mile?
How do I convert miles to nautical miles?
How do I convert nautical miles back to miles?
How many nautical miles is 100 miles?
Popular length unit conversions
Convert Mile to other length units
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Metric / SI (18 units)
Imperial / US Customary (26 units)
Nautical (1 units)
Astronomical (9 units)
Atomic / Physics (6 units)
Typographic (3 units)
Sources & references
Conversion factor (1 mi = 0.8689762419 nmi) verified against the following authoritative sources:
- BIPM — The International System of Units (SI Brochure 9th ed.)
Official BIPM publication defining the seven SI base units (including the meter) and the rules for their use. The global authority on units of measurement.
- NIST — Guide to the SI
US National Institute of Standards and Technology reference covering the SI base and derived units with definitions and usage rules for US technical practice.
- NIST Special Publication 811 — Guide for the Use of the International System of Units
Detailed NIST guide covering exact conversion factors between SI and US customary units along with formatting and rounding conventions.
- NIST — Refinement of values for the yard and pound (Federal Register 1959)
The treaty (signed by US
- International Hydrographic Organization — Resolution on the Nautical Mile
International authority that standardised the nautical mile at exactly 1852 m in 1929 — the value adopted worldwide for sea and air navigation.