Knots to km/h converter
1 knot = 1.852 km/h — exactly one nautical mile per hour. Enter knots for km/h, or the other way round.
1 kn = 1.9 km/h · 1 km/h = 0.5 kn
Knots to km/h table
| Knots | km/h |
|---|---|
| 1 kn | 1.9 km/h |
| 5 kn | 9.3 km/h |
| 10 kn | 18.5 km/h |
| 15 kn | 27.8 km/h |
| 20 kn | 37 km/h |
| 25 kn | 46.3 km/h |
| 30 kn | 55.6 km/h |
| 34 kn | 63 km/h |
| 40 kn | 74.1 km/h |
| 50 kn | 92.6 km/h |
| 64 kn | 118.5 km/h |
| 100 kn | 185.2 km/h |
34 kn = start of gale force 8 · 64 kn = hurricane force 12.
Beaufort scale: knots and km/h
| Beaufort | Description | knots | km/h |
|---|---|---|---|
| 3 | gentle breeze | 7–10 | 12–19 |
| 4 | moderate breeze | 11–16 | 20–28 |
| 6 | strong breeze | 22–27 | 39–49 |
| 8 | gale | 34–40 | 62–74 |
| 10 | storm | 48–55 | 89–102 |
| 12 | hurricane | ≥ 64 | ≥ 118 |
Marine forecasts give wind in knots; most land forecasts use km/h — hence this conversion. The matching distance unit is the nautical mile (1.852 km).
Why "knots"? The log line
The name is literal: sailors threw a wooden "log" overboard on a knotted line and counted how many knots ran through their hands while a 28-second sandglass emptied. The knot spacing was chosen so the count equalled nautical miles per hour. Aviation kept the unit: airliners rotate at ~150 kn and cruise at 450–500 kn true airspeed, and METAR wind reports are in knots too.
Frequently asked questions
How many km/h is one knot?
1 knot = 1.852 km/h — one nautical mile per hour. Quick rule: double the knots and subtract 10 % — 20 kn is about 37 km/h.
Why do ships and planes measure speed in knots?
The nautical mile equals one minute of latitude, so charts and knots fit together for navigation. The name comes from the knotted log line sailors paid out to measure speed.
How fast are typical ships and winds?
Sailing yacht: 5–8 kn (9–15 km/h), ferry: 15–25 kn, container ship: ~20 kn (37 km/h). Gale force 8 starts at 34 kn (63 km/h); hurricane force 12 at 64 kn (118 km/h).
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