kilometer per hour to kilometer per second
Convert kilometer per hour (km/h) to kilometer per second (km/s). Use an editable speed converter, conversion formula, and reference table.
1 km/h = 0.0002777777778 km/s
Conversion formula
One kilometer per hour equals 0.0002777777778 kilometer per second. Multiply your value in kilometer per hour by this factor to get kilometer per second. For the reverse conversion, divide by the same factor.
Worked example
To convert 5 kilometer per hour:5 × 0.0002777777778 = 0.001388888889 km/s
Conversion table
| kilometer per hour (km/h) | kilometer per second (km/s) |
|---|---|
| 0.01 | 0.000002777777778 |
| 0.1 | 0.00002777777778 |
| 1 | 0.0002777777778 |
| 2 | 0.0005555555556 |
| 5 | 0.001388888889 |
| 10 | 0.002777777778 |
| 25 | 0.006944444444 |
| 50 | 0.01388888889 |
| 100 | 0.02777777778 |
| 1000 | 0.2777777778 |
About these measurements
Speed is distance traveled per unit of time.
The base reference used here is the meter per second. One kilometer per hour is 0.2777777778 base units; one kilometer per second is 1,000 base units.
Important distinctions
Mach is excluded because the speed of sound depends on medium and temperature.
Precision
The converter uses stored conversion factors and floating-point arithmetic. Results display up to ten significant digits, switching to scientific notation for very small or large values. Keep the precision of your original measurement when reporting results.
Common questions
How do I convert km/h to km/s?
Multiply the quantity in km/h by 0.0002777777778. You can also type the value into the converter above.
Can I reverse the conversion?
Yes. Use the swap button or open the kilometer per second to kilometer per hour converter.
Reference
NIST Guide to the SI — conversion factors and prefix conventions. SI prefixes scale units by powers of ten; the dimension-specific notes above describe the assumptions used on this page.
