Kilometers per second to kilometers per hour
Type a value in kilometers per second to see it in kilometers per hour straight away, or type in the second box to convert back.
Loading the tool…
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 second box.
- Read the result in kilometers per hour as you type, and pick the precision you need.
- Swap the direction to convert back, or copy the result.
How it is calculated
km/h = km/s × 3,600
Multiply the value in kilometers per second by 3,600 to get kilometers per hour.
Example
To convert 25 km/s to kilometers per hour: 25 × 3,600 = 90,000 km/h.
Conversion table
| Kilometers per second (km/s) | Kilometers per hour (km/h) |
|---|---|
| 1 | 3,600 |
| 2 | 7,200 |
| 3 | 10,800 |
| 5 | 18,000 |
| 10 | 36,000 |
| 20 | 72,000 |
| 25 | 90,000 |
| 50 | 180,000 |
| 100 | 360,000 |
| 250 | 900,000 |
| 500 | 1,800,000 |
| 1,000 | 3,600,000 |
About the units
- Kilometer per second
- Covering 1000 meters in one second. It is used for satellites, rockets and astronomical objects.
- 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.
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 kilometers per hour are in one kilometer per second?
1 km/s = 3,600 km/h exactly.
How do I convert kilometers per second to kilometers per hour?
Use km/h = km/s × 3,600. For example, 25 km/s = 90,000 km/h.
How many kilometers per second are in one kilometer per hour?
1 km/h = 0.000277778 km/s.
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.