Nautical Mile Calculator
Convert nautical miles to kilometres, statute miles, metres, and feet — and calculate travel time for any distance at a given speed in knots.
nautical miles
knots
1 nautical mile = 1.852 km exactly (international definition)
- 1
Convert to metres
100 × 1,852 = 185,200 - 2
Kilometres
185,200 ÷ 1,000 = 185.2001 nautical mile = 1,852 m exactly; dividing by 1,000 gives kilometres.
How does this calculator work?
One nautical mile = 1,852 m = 1.852 km = 1.15078 statute miles = 6,076 ft. Travel time = distance (nm) ÷ speed (knots). Nautical miles are used at sea and in aviation because 1 nm = 1 arc-minute of latitude, making chart navigation direct. 1 knot = 1.852 km/h.
Formula
How this is calculated
A nautical mile (nmi) is exactly 1,852 metres by international definition, adopted in 1929. It was originally defined as one minute of arc of latitude along a meridian of the Earth, which is what makes it so useful at sea and in aviation: one degree of latitude equals exactly 60 nautical miles, so positions read directly off a nautical chart without any conversion. A boat doing 15 knots covers 15 × 1,852 = 27,780 metres per hour.
The conversion to statute (land) miles uses the exact definition 1 statute mile = 1,609.344 m, giving 1 nmi ≈ 1.15078 mi. The conversion to feet uses 1 ft = 0.3048 m exactly, giving 1 nmi = 6,076.115 ft. Travel time is the simplest navigation formula: Time (h) = Distance (nmi) ÷ Speed (knots). Because knots already express speed in nautical miles per hour, there is no further unit conversion needed.
The number line below shows the same distance expressed as nautical miles, statute miles, and kilometres side by side, illustrating that 1 nmi produces three different numbers in three different units — with km always the largest (1.852), nmi the smallest (1), and statute miles in between (1.151).
Frequently asked questions
A nautical mile equals exactly one arc-minute of latitude. That direct link to angular measurement makes nautical miles readable straight from a navigation chart — one degree of latitude = 60 nm — simplifying chart work and celestial navigation. Aviation inherited the convention from maritime practice.
One knot is one nautical mile per hour. To convert knots to km/h, multiply by 1.852. To convert to statute mph, multiply by 1.15078. The name "knot" comes from the historical chip-log, where sailors measured speed by counting knots in a rope as it played out over the stern.
Exactly 60 nautical miles, by definition. The full polar circumference of the Earth is 360° × 60 = 21,600 nmi ≈ 40,003 km — which is also close to the original metric definition of the kilometre (one ten-thousandth of the distance from pole to equator).
Also known as
TG we-Calculate Editorial Team. (2026). Nautical Mile Calculator [Online calculator]. TG we-Calculate. https://we-calculate.com/calculator/nautical-mile-calculator
TG we-Calculate Editorial Team. "Nautical Mile Calculator." TG we-Calculate. 2026. https://we-calculate.com/calculator/nautical-mile-calculator.
TG we-Calculate Editorial Team, "Nautical Mile Calculator," TG we-Calculate, 2026. [Online]. Available: https://we-calculate.com/calculator/nautical-mile-calculator
@misc{wecalculate_nautical_mile_calculator, title = {Nautical Mile Calculator}, author = {{TG we-Calculate Editorial Team}}, howpublished = {\url{https://we-calculate.com/calculator/nautical-mile-calculator}}, year = {2026}, note = {TG we-Calculate} }
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