KM/H to M/S Calculator — Convert Kilometres per Hour to Metres per Second
Use this free km/h to m/s calculator to instantly convert kilometres per hour to metres per second. Results also show mph and knots. Used in physics, engineering and science where m/s is the standard SI unit of speed.
How to Convert KM/H to M/S
To convert kilometres per hour to metres per second, divide the speed by 3.6. This works because there are 1,000 metres in a kilometre and 3,600 seconds in an hour — so 1 km/h equals exactly 1/3.6 m/s.
To convert back from m/s to km/h, simply multiply by 3.6.
Common KM/H to M/S Conversions
Here are the most frequently needed km/h to m/s conversions for quick reference:
| Kilometres per Hour (km/h) | Metres per Second (m/s) | Miles per Hour (mph) |
|---|---|---|
| 10 km/h | 2.78 m/s | 6.21 mph |
| 30 km/h | 8.33 m/s | 18.64 mph |
| 50 km/h | 13.89 m/s | 31.07 mph |
| 60 km/h | 16.67 m/s | 37.28 mph |
| 80 km/h | 22.22 m/s | 49.71 mph |
| 100 km/h | 27.78 m/s | 62.14 mph |
| 120 km/h | 33.33 m/s | 74.56 mph |
| 200 km/h | 55.56 m/s | 124.27 mph |
When Would You Need to Convert KM/H to M/S?
KM/H is the everyday unit for speed on roads and transport, while M/S is the standard unit used in science, physics and engineering. Converting between them comes up in many situations:
KM/H vs M/S — What's the Difference?
Both units measure the same thing — how fast something is moving — but they're used in different contexts:
- KM/H (kilometres per hour) — the everyday speed unit used on road signs, speedometers and weather reports in most countries
- M/S (metres per second) — the SI base unit for speed, used in science, physics, engineering and academic contexts worldwide
- 1 m/s is equal to 3.6 km/h — so speeds in m/s are always a smaller number than the same speed in km/h
- The speed of light is approximately 299,792,458 m/s or about 1,079,252,849 km/h
FAQs
How do I convert km/h to m/s?
Divide the speed in km/h by 3.6 to get m/s. For example, 72 km/h ÷ 3.6 = 20 m/s.
What is 100 km/h in m/s?
100 km/h is equal to 27.78 m/s. This is a common conversion used in physics problems and engineering calculations.
What is 60 km/h in m/s?
60 km/h is equal to 16.67 m/s. This is a typical urban speed limit in many countries.
Why do we divide by 3.6 to convert km/h to m/s?
Because 1 kilometre = 1,000 metres and 1 hour = 3,600 seconds. So 1 km/h = 1,000/3,600 m/s = 1/3.6 m/s. Dividing by 3.6 converts the units correctly.
What is 120 km/h in m/s?
120 km/h is equal to 33.33 m/s. This is a common motorway speed limit in many European countries.
Is this calculator free?
Yes — completely free, no sign-up required. Use it as many times as you need on any device.