Kilometers per Hour to Meters per Second
Convert kilometers per hour (km/h) to meters per second (m/s). Both measure velocity, and the conversion comes up in driving, aviation, sports work.
The Formula
``
meters per second = kilometers per hour × 0.277777777778
kilometers per hour = meters per second × 3.6
`
One kilometers per hour is 0.277778 meters per second, and one meters per second is 3.6 kilometers per hour.
Conversion Table
| Kilometers per Hour | Meters per Second |
|---|---|
| 1 km/h | 0.277778 m/s |
| 2 km/h | 0.555556 m/s |
| 5 km/h | 1.3889 m/s |
| 10 km/h | 2.7778 m/s |
| 25 km/h | 6.9444 m/s |
| 50 km/h | 13.8889 m/s |
| 100 km/h | 27.7778 m/s |
| 500 km/h | 138.8889 m/s |
| 1,000 km/h | 277.7778 m/s |
The Other Direction
| Meters per Second | Kilometers per Hour |
|---|---|
| 1 m/s | 3.6 km/h |
| 2 m/s | 7.2 km/h |
| 5 m/s | 18 km/h |
| 10 m/s | 36 km/h |
| 25 m/s | 90 km/h |
| 50 m/s | 180 km/h |
| 100 m/s | 360 km/h |
| 500 m/s | 1,800 km/h |
| 1,000 m/s | 3,600 km/h |
What Each Unit Is
Kilometers per Hour (km/h) — kilometres travelled per hour, equal to 1/3.6 m/s. The road-speed unit in almost every country outside the US and UK.
Meters per Second (m/s) — the SI unit of speed — metres travelled per second. The coherent SI derived unit, used throughout physics and engineering.
A Sense of Scale
Urban limits are 30–50 km/h- Motorways are 100–130 km/h
- A cyclist cruises at 20 km/h
- Walking is 1.4 m/s
- A sprinter peaks near 12 m/s
- Sound travels at 343 m/s
Precision
The factor 0.277777777778 is rounded. For engineering work carry more digits than the table above, and round only at the end — rounding at each step compounds.
In Code
`javascript
const kilometerPerHourToMeterPerSecond = (value) => value * 0.277777777778;
``
Where This Conversion Comes Up
- Driving
- Aviation
- Sports
- Shipping
- Weather
How Many Decimals Do You Need?
Rounding the factor costs accuracy, and how much depends on the factor. Converting 137 km/h with the factor truncated at each decimal place:
| Decimals kept | Factor | 137 km/h becomes | Error |
|---|---|---|---|
| 0 | 0 | 0 | 100.0000% |
| 1 | 0.3 | 41.1 | 8.0000% |
| 2 | 0.28 | 38.36 | 0.8000% |
| 3 | 0.278 | 38.086 | 0.0800% |
| 4 | 0.2778 | 38.0586 | 0.0080% |
The right number of significant figures is set by your input, not by the converter. If you measured kilometers per hour to three significant figures, the answer in meters per second is only good to three — writing more digits claims precision the measurement never had.