Unit converter
Nautical Miles to Kilometers Converter
Change nautical miles into kilometres at a glance. The international nautical mile is defined as exactly 1852 metres, which is 1.852 kilometres, a value agreed in 1929 and tied to one minute of latitude. Feed a distance in nautical miles into the tool and it shows kilometres along with a table of common figures. This conversion matters for reading marine and aviation charts in metric, comparing a ship or aircraft range against road distances, planning a sailing passage, or making sense of weather and shipping forecasts that mix the two units.
1 nautical mile = 1.852 kilometers
Common nautical miles to kilometers values
| Nautical miles | Kilometers |
|---|---|
| 1 nmi | 1.852 km |
| 2 nmi | 3.704 km |
| 5 nmi | 9.26 km |
| 10 nmi | 18.52 km |
| 20 nmi | 37.04 km |
| 50 nmi | 92.6 km |
| 100 nmi | 185.2 km |
How to convert
- Take the distance given in nautical miles.
- Multiply it by 1.852, as one nautical mile is exactly 1.852 kilometres.
- The result is that distance expressed in kilometres.
- Divide kilometres by 1.852 to convert back to nautical miles.
- For a rough figure, add about 85 percent to the nautical mile count: 10 nautical miles is near 18.5 km, and 100 is about 185 km.
kilometres = nautical miles × 1.852
The international nautical mile is fixed at exactly 1852 metres, which is 1.852 kilometres, so multiplying a nautical-mile figure by 1.852 gives kilometres. Dividing kilometres by 1.852 reverses it. The constant is exact, leaving rounding only to your chosen decimals.
- nmi
- the distance in nautical miles you start with
- 1.852
- kilometres in one nautical mile, by definition
Worked example
A 12-nautical-mile territorial sea limit comes to 12 multiplied by 1.852, which is exactly 22.224 kilometres. A coastal passage of 50 nautical miles equals 50 times 1.852, or 92.6 km, useful when matching a sailing leg to a land map.
Key facts
- One nautical mile is exactly 1.852 km; one kilometre is about 0.54 nautical miles.
- A nautical mile is roughly 1.15 statute miles, longer than the land mile.
- The unit equals one minute of arc of latitude on the Earth.
- A 200-nautical-mile exclusive economic zone reaches about 370.4 km offshore.
Tips
- On a marine chart, read distance off the latitude scale, where one minute equals one nautical mile.
- To picture knots in metric, multiply the knot figure by 1.852 to get km/h directly.
- Carry the full 1.852 factor and round only the final kilometre value for long passages.
Frequently asked questions
How many kilometres are in 1 nautical mile?+
Exactly 1.852 kilometres, or 1852 metres, by international definition since 1929.
How many nautical miles is 100 km?+
Divide 100 by 1.852 to get about 53.996 nautical miles, just under 54.
Why is a nautical mile longer than a land mile?+
It is set to one minute of latitude along a meridian, which makes it about 1.15 statute miles rather than the 1.609 km of a land mile.
Is a knot one nautical mile per hour?+
Yes. A knot is exactly one nautical mile per hour, so 10 knots is 18.52 km/h.
Things to watch
- The nautical mile is not the statute mile; treating 1 nmi as 1.609 km understates the distance by roughly 15 percent.
Sources
Last updated: 2026-01-01
Conversions use internationally defined factors. Provided for general use; verify critical measurements independently.