Knots to km/h
km/h = knots × 1.852
Exact factor: 1 nautical mile = 1,852 m.
Convert knots to km/h (and km/h to knots)
Two-way knots ↔ km/h converter: exact factor (1 knot = 1 nautical mile per hour = 1.852 km/h), formulas, a mental-math shortcut, Beaufort scale reference points and real examples (sailboat, airliner, wind gusts).
Conversion table
| kn | km/h |
|---|---|
| 1 kn | 1.852 km/h |
| 2 kn | 3.704 km/h |
| 5 kn | 9.26 km/h |
| 10 kn | 18.52 km/h |
| 20 kn | 37.04 km/h |
| 50 kn | 92.6 km/h |
| 100 kn | 185.2 km/h |
| 1,000 kn | 1,852 km/h |
| km/h | kn |
|---|---|
| 1 km/h | 0.54 kn |
| 2 km/h | 1.07991 kn |
| 5 km/h | 2.69978 kn |
| 10 km/h | 5.39957 kn |
| 20 km/h | 10.7991 kn |
| 50 km/h | 26.9978 kn |
| 100 km/h | 53.9957 kn |
| 1,000 km/h | 539.957 kn |
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How does this tool work?
This converter turns knots (kn) into kilometers per hour (km/h) and back: type a speed in either field and the other updates instantly. The knot is the speed unit of marine and air navigation, so you need it to read a marine forecast, a sailboat or ferry speed, an aircraft speed, or wind data on a forecast site for sailing, kitesurfing or paragliding.
One knot is one nautical mile per hour. The international nautical mile has been exactly 1,852 m since the 1929 International Hydrographic Conference; historically it matches one minute of arc of latitude. So 1 knot = 1.852 km/h exactly, and 1 km/h ≈ 0.539957 knot.
To go from knots to km/h, multiply by 1.852; to go from km/h to knots, divide by 1.852. For example, 25 knots × 1.852 = 46.3 km/h, and 100 km/h ÷ 1.852 ≈ 54 knots. In meters per second, 1 knot ≈ 0.514 m/s, roughly half the knot figure.
In your head, double the knots and take away 10%: 20 knots ≈ 36 km/h (exact 37.04), an estimate about 3% low. The other way, halve the km/h and add 8%: 100 km/h ≈ 54 knots.
A knot is already a speed, so "knots per hour" is a mistake. Do not confuse it with mph either, which is based on the 1,609.344 m statute mile: 1 knot ≈ 1.151 mph. Finally, the Beaufort scale groups wind into ranges of knots, not exact values.
How to use this tool
Enter a speed
Type a speed in knots from a forecast or a GPS, or a speed in km/h; decimals are accepted.
Read the conversion
The other field updates on every keystroke; for wind, rounding to the nearest knot or km/h is plenty.
Spot the wind thresholds
The table below the converter lists common speeds, including Beaufort thresholds such as 34 knots (gale) and 64 knots (hurricane force).
Knots ↔ km/h conversion formulas
The knot is defined from the international nautical mile of 1,852 m.
km/h to knots
knots = km/h ÷ 1.852 ≈ km/h × 0.539957
0.539957 is rounded to six decimals.
Knots to m/s
m/s = knots × 1,852 ÷ 3,600 ≈ knots × 0.514444
Useful for anemometers and scientific data in m/s.
- v knots
- speed in knots (nautical miles per hour)
- v km/h
- speed in kilometers per hour
- v m/s
- speed in meters per second
Example: a 15-knot wind = 15 × 1.852 = 27.78 km/h, about 7.7 m/s.
Use cases
Sailing and boating
Convert the boat speed shown by the log or GPS and give passengers a passage time they can relate to.
Wind forecasts
Compare a marine forecast in knots with a land forecast in km/h before a kitesurf, windsurf or paragliding session.
Aviation
Translate takeoff, cruise or surface wind speeds given in knots by air traffic control and charts.
Shipping
Understand the service speed of a ferry or container ship, usually between 15 and 25 knots.
Examples
Cruising sailboat
6 × 1.852 = 11.112 km/h, a typical upwind speed for a 33-foot sailboat.
Input
6 knotsResult
11.11 km/hKitesurfing wind
20 × 1.852 = 37.04 km/h, a fresh breeze, force 5 on the Beaufort scale.
Input
20 knotsResult
37.04 km/hGale warning
34 × 1.852 ≈ 62.97 km/h (about 39 mph): the start of force 8, when marine forecasts issue a gale warning.
Input
34 knotsResult
62.97 km/hAirliner at cruise
480 × 1.852 = 888.96 km/h true airspeed, before accounting for winds aloft.
Input
480 knotsResult
888.96 km/hGust reported in km/h
100 ÷ 1.852 ≈ 54.00 knots, which is force 10 (storm) at sea.
Input
100 km/hResult
54 knotsTips and best practices
- Quick anchors: 10 knots ≈ 18.5 km/h, 30 knots ≈ 55.6 km/h, 50 knots ≈ 92.6 km/h.
- Forecast sites often let you pick the unit: check whether a figure is the mean wind or the gusts.
- One knot is about 0.514 m/s: halve the knots for a quick m/s estimate.
- For passage planning, a distance in nautical miles divided by the speed in knots gives hours directly.
- For road speeds in miles, use the km/h ↔ mph converter instead.
Sources and references
Frequently asked questions
How many km/h is one knot?
One knot is exactly 1.852 km/h, because it is one nautical mile (1,852 m) covered in one hour.
What is 20 knots in km/h?
20 knots is 37.04 km/h (20 × 1.852), or about 23 mph. That is force 5 on the Beaufort scale.
How do I convert km/h to knots?
Divide by 1.852 or multiply by 0.539957. For example, 50 km/h ≈ 27 knots and 900 km/h ≈ 486 knots.
Why are speeds at sea measured in knots?
Sailors used to throw a chip log tied to a line with evenly spaced knots and count how many ran out in a set time. The nautical mile, tied to latitude, also makes chart navigation easier.
How fast is hurricane-force wind in km/h?
Force 12 on the Beaufort scale starts at 64 knots, about 118.5 km/h (64 × 1.852 = 118.53 km/h) or 74 mph.
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