Knots / km/h Conversion Calculator
Written by Thierno Sadou Diallo, formula verified per our methodology • Last checked on 9/10/2026
One knot equals exactly 1.852 km/h. To convert knots to km/h, multiply by 1.852; to convert km/h to knots, divide by 1.852.
Explanation
The knot is the reference speed unit in maritime navigation and aviation, as well as in meteorology for expressing wind speed. It corresponds to a speed of one nautical mile per hour, the nautical mile itself being defined as the length of one arcminute of an Earth meridian — a definition that links it directly to the geometry of the globe, convenient for navigation (a distance traveled in nautical miles corresponds directly to a displacement in minutes of latitude). Since 1929, the international nautical mile has been fixed at exactly 1,852 meters, which gives an exact equivalence of 1 knot = 1.852 km/h — unlike most unit conversions, which rely on approximate or irrational factors, this one is a round number defined by international convention, with no uncertainty. The use of the knot persists today in shipping and aviation despite the spread of the metric system, largely because nautical and aeronautical charts remain graduated in nautical miles and arcminutes, making the knot more practical for navigation than km/h in that specific context.
Example: 10 knots to km/h
Inputs
Value: 10 knots. Direction: knots → km/h.
Calculation
10 knots × 1.852 = 18.52 km/h.
Result
A speed of 10 knots equals 18.52 km/h.
Frequently asked questions
Why do shipping and aviation still use knots rather than km/h?
Because the knot is directly tied to the nautical mile, a distance unit itself linked to Earth's geometry (one arcminute of meridian) and used on nautical and aeronautical charts. Navigating in knots and nautical miles simplifies position and travel-time calculations on those charts, a practical advantage that has kept this unit in use despite the spread of the metric system elsewhere.
Is the equivalence 1 knot = 1.852 km/h a rounded value?
No, it's an exact value: the international nautical mile was fixed at exactly 1,852 meters by convention in 1929, which makes the conversion to knots perfectly exact, with no rounding or approximation — a fairly rare case among unit conversions, most of which rely on non-round factors.
Is the knot also used to measure wind speed?
Yes, it's the standard unit in marine and aeronautical weather bulletins for expressing wind speed, particularly in forecasts intended for sailors and pilots. The general public more often encounters wind speed in km/h in mainstream weather forecasts, which may require this conversion to compare the two sources.