Kilometers per hour to knots
Type a value in kilometers per hour to see it in knots straight away, or type in the second box to convert back.
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Processing and privacy: The result is calculated inside your browser and your data is not sent to any server.
How to use it
- Type the value in the kilometers per hour box.
- Read the result in knots as you type, and pick the precision you need.
- Swap the direction to convert back, or copy the result.
How it is calculated
kn = km/h × 0.5399568035
Multiply the value in kilometers per hour by 0.5399568035 to get knots.
Example
To convert 25 km/h to knots: 25 × 0.5399568035 = 13.4989 kn.
Conversion table
| Kilometers per hour (km/h) | Knots (kn) |
|---|---|
| 1 | 0.539957 |
| 2 | 1.07991 |
| 3 | 1.61987 |
| 5 | 2.69978 |
| 10 | 5.39957 |
| 20 | 10.7991 |
| 25 | 13.4989 |
| 50 | 26.9978 |
| 100 | 53.9957 |
| 250 | 134.989 |
| 500 | 269.978 |
| 1,000 | 539.957 |
About the units
- Kilometer per hour
- Covering 1000 meters in 3600 seconds, so 1 km/h is exactly 1/3.6 m/s. It is the unit on road signs and car speedometers in most countries.
- Knot
- One nautical mile (1852 m) per hour, about 0.514444 m/s. It is the speed unit of aviation, shipping and wind reports.
Limits and caveats
- Results are rounded for display and computed with the browser's floating point precision (about 15 significant digits).
- Both unit factors are exact by their official definitions.
Questions about this tool
How many knots are in one kilometer per hour?
1 km/h = 0.539957 kn exactly.
How do I convert kilometers per hour to knots?
Use kn = km/h × 0.5399568035. For example, 25 km/h = 13.4989 kn.
How many kilometers per hour are in one knot?
1 kn = 1.852 km/h.
How do I convert km/h to m/s in my head?
Divide by 3.6, because an hour is 3600 seconds and a kilometer is 1000 meters. For example 72 km/h is 20 m/s; multiply by 3.6 to go back.
Why do Mach values differ between sources?
The speed of sound depends on air temperature. We use 340.294 m/s at sea level and 15 °C; at 11 km altitude it is about 295 m/s, so Mach 1 is slower there.