Convert knots to kilometers per hour
One knot (kn) equals 1.852 kilometers per hour (km/h), so multiply knots by 1.852 to get kilometers per hour.
How do you convert knots to kilometers per hour?
Is a knot the same as a kilometre per hour?
No. One knot is one nautical mile per hour, and the international nautical mile is exactly 1,852 metres, so 1 knot is exactly 1.852 km/h. A speed in knots therefore becomes a km/h figure about 85 percent larger: 10 knots is 18.52 km/h and 25 knots is 46.3 km/h. Reading a knot as a kilometre per hour understates a wind or a vessel by nearly half.
There is no such thing as knots per hour
The per-hour is already inside the unit. A knot is a nautical mile per hour, so knots per hour would describe an acceleration rather than a speed. A ship holding 12 knots is covering 12 nautical miles every hour, which is 22.22 km/h, and it holds that speed rather than gaining it.
Why exactly 1,852 metres
The nautical mile began as one minute of arc of latitude, which varies slightly with the shape of the Earth, so an international conference in Monaco in 1929 fixed it at exactly 1,852 metres. That definition is what makes the knot convert exactly rather than approximately, and it is why one degree of latitude is still 60 nautical miles on any chart.
Knots to km/h and knots to mph are not the same step
A knot is 1.852 km/h but only 1.150779 mph, because a statute mile is longer than a kilometre. So a 40-knot gale is 74.08 km/h and 46.03 mph at the same time, and quoting the wrong one either exaggerates or flattens the wind by more than half. Both conversions are exact, which is why it is worth stating which unit an answer is in.
Reading a marine or aviation forecast
Wind, current and vessel speeds are given in knots throughout marine and aviation practice, and the thresholds are set there too: the National Hurricane Center puts the category 1 boundary at 64 knots, which it lists as 119 km/h and 74 mph. Converting the knots figure is usually the last step before a chart, a METAR or a storm bulletin makes sense to a road-going audience.
Knots in kilometres per hour, miles per hour and metres per second
Calculated from the exact definitions: 1 knot is 1.852 km/h, 1.150779 mph and 0.514444 m/s. The 64-knot row is the National Hurricane Center's category 1 threshold.
| Knots | Kilometres per hour | Miles per hour | Metres per second |
|---|---|---|---|
| 1 kn | 1.85 km/h | 1.15 mph | 0.51 m/s |
| 2 kn | 3.7 km/h | 2.3 mph | 1.03 m/s |
| 3 kn | 5.56 km/h | 3.45 mph | 1.54 m/s |
| 5 kn | 9.26 km/h | 5.75 mph | 2.57 m/s |
| 10 kn | 18.52 km/h | 11.51 mph | 5.14 m/s |
| 15 kn | 27.78 km/h | 17.26 mph | 7.72 m/s |
| 20 kn | 37.04 km/h | 23.02 mph | 10.29 m/s |
| 25 kn | 46.3 km/h | 28.77 mph | 12.86 m/s |
| 30 kn | 55.56 km/h | 34.52 mph | 15.43 m/s |
| 35 kn | 64.82 km/h | 40.28 mph | 18.01 m/s |
| 40 kn | 74.08 km/h | 46.03 mph | 20.58 m/s |
| 50 kn | 92.6 km/h | 57.54 mph | 25.72 m/s |
| 60 kn | 111.12 km/h | 69.05 mph | 30.87 m/s |
| 64 kn | 118.53 km/h | 73.65 mph | 32.92 m/s |
| 80 kn | 148.16 km/h | 92.06 mph | 41.16 m/s |
| 100 kn | 185.2 km/h | 115.08 mph | 51.44 m/s |
Sources
Knot to kilometer per hour conversion table
| Knots | Kilometers per hour | Kilometers per hour | Knots |
|---|---|---|---|
| 1 kn | 1.852 km/h | 1 km/h | 0.539957 kn |
| 2 kn | 3.704 km/h | 2 km/h | 1.0799 kn |
| 3 kn | 5.556 km/h | 3 km/h | 1.6199 kn |
| 5 kn | 9.26 km/h | 5 km/h | 2.6998 kn |
| 10 kn | 18.52 km/h | 10 km/h | 5.3996 kn |
| 20 kn | 37.04 km/h | 20 km/h | 10.7991 kn |
| 50 kn | 92.6 km/h | 50 km/h | 26.9978 kn |
| 100 kn | 185.2 km/h | 100 km/h | 53.9957 kn |
| 500 kn | 926 km/h | 500 km/h | 269.98 kn |
| 1000 kn | 1852 km/h | 1000 km/h | 539.96 kn |
To convert knots to kilometers per hour, multiply the number of knots by 1.852. One knot equals 1.852 kilometers per hour, and one kilometer per hour equals 0.539957 knots, so the relationship is fixed and exact. As a worked example, 10 kn comes to 18.52 km/h. Enter your own figure in the converter above to get an instant answer, or use the swap button to flip the direction. This is a speed conversion, and like every tool on UnitGlide it runs locally in your browser with no account or upload required. The table further down shows a range of common knot values already worked out in kilometers per hour, plus the reverse kilometer per hour to knot direction, which is handy for quick reference or double-checking a result by hand.
Knot to kilometer per hour in practice
Knots to kilometres per hour is the conversion that translates a boat, an aircraft or a storm from the world of nautical charts into the km/h a land-based audience understands.
At sea, in the air and in the forecast
Ships and aircraft report speed in knots, and so do marine and tropical-storm warnings. A cruising yacht at 6 knots is doing 11.1 km/h, an airliner at 500 knots is at 926 km/h, and a hurricane's 90-knot sustained winds are 167 km/h. Converting to km/h is usually about making those figures legible to people who never read a chart or a METAR.
Why the unit is called a knot
The name comes from the chip log, a weighted board streamed on a line with knots tied at fixed intervals along it. The crew let the line run out behind the ship for the length of a sand glass and counted the knots that passed through their hands, which gave the speed directly with no arithmetic at all. The instrument disappeared long ago; the word and the unit stayed.
A deck-side estimate
The exact factor is 1.852, so a knot is a little under two km/h. For a rough estimate on deck, doubling the knots and trimming a little works: 20 knots doubled is 40, and the true answer is 37 km/h. For anything navigational, use the full factor rather than the round double.
Speed through water, not over the ground
A boat's log measures its speed through the water it is sitting in, which is not the same as its progress across the seabed once a current is involved. A yacht showing 7 knots into a 2-knot foul tide is only making 5 knots over the ground, or 9.26 km/h instead of 12.96 km/h. Converting the figure is easy; knowing which of the two speeds you were handed is the part that matters.
Frequently asked questions
How fast is 10 knots in km/h?
10 knots is exactly 18.52 km/h, which is 11.51 mph. Multiply knots by 1.852 for km/h, or by 1.150779 for mph.
Is a knot faster than a kilometre per hour?
Yes, by a factor of 1.852. One knot covers 1,852 metres in an hour against the kilometre per hour's 1,000 metres, so any speed in knots is a smaller number than the same speed in km/h.
Why do ships and aircraft still use knots?
Because a nautical mile is one minute of latitude, so a speed in knots relates directly to distance measured off a chart. Sixty nautical miles is one degree of latitude, which makes navigation arithmetic simple in a way that kilometres do not.
How many kilometers per hour are in a knot?
One knot equals 1.852 kilometers per hour. The ratio is constant, so you can multiply any number of knots by 1.852 to get kilometers per hour.
What is the formula to convert knots to kilometers per hour?
Use kilometers per hour = knots × 1.852. UnitGlide applies this exact formula for every value, so results stay accurate across the whole range.
How do I convert kilometers per hour back to knots?
Go the other way by using one kilometer per hour equals 0.539957 knots. You can also press the swap button in the converter above to flip the direction in one click.
Is this knot to kilometer per hour converter accurate?
Yes. It uses internationally defined SI conversion factors, as maintained by the BIPM, and all math runs in your browser so nothing is rounded away on a server. For everyday use the displayed precision is more than enough.