Where each speed unit is used
- Kilometers per hour (km/h) for road speeds in most of the world.
- Miles per hour (mph) for road speeds in the United States and the United Kingdom.
- Meters per second (m/s) in science and in many wind forecasts.
- Knots (kn) at sea, in aviation and for wind at sea. One knot is one nautical mile per hour, or 1.852 km/h.
- Feet per second (ft/s) in engineering and ballistics in the US.
Common speed conversions
| From | Equals |
|---|---|
| 1 kilometer per hour | 0.6213711922 miles per hour |
| 1 mile per hour | 1.609344 kilometers per hour |
| 1 meter per second | 3.6 kilometers per hour |
| 1 knot | 1.852 kilometers per hour |
| 1 knot | 1.150779448 miles per hour |
| 1 meter per second | 2.236936292 miles per hour |
| 1 foot per second | 0.3048 meters per second |
km/h to mph chart
| Kilometers per hour (km/h) | Miles per hour (mph) |
|---|---|
| 10 | 6.214 |
| 20 | 12.43 |
| 30 | 18.64 |
| 40 | 24.85 |
| 50 | 31.07 |
| 60 | 37.28 |
| 70 | 43.5 |
| 80 | 49.71 |
| 90 | 55.92 |
| 100 | 62.14 |
| 110 | 68.35 |
| 120 | 74.56 |
| 130 | 80.78 |
| 150 | 93.21 |
| 200 | 124.3 |
Where the conversions come up
Driving abroad is the classic: a 70 mph limit on a British motorway is 113 km/h, and a 130 kmh sign on a German autobahn is 81 mph. Treadmills and running apps mix minutes per mile, minutes per kilometer and km/h. Wind speed turns up as knots in a sailing forecast, as m/s in a European weather report and as mph in an American one. And a bike computer will happily show whichever unit you did not set it to.
Shortcuts: km/h to mph is times 0.6, mph to km/h is times 1.6. For m/s to km/h multiply by 3.6, and a knot is about 1.15 mph or 1.85 km/h. Velocity in physics problems is almost always in m/s, which is why that unit is in the list.
How to use it
- 1The page opens with km/h to mph. Change either dropdown for knots, m/s or ft/s.
- 2Type the speed on either side. The other side updates while you type, and swap reverses the direction.
- 3Under the result you get the factor and the same speed in all five units. Copy the number or a link to this exact conversion.
Frequently asked questions
How many mph is 100 km/h?
About 62.14 mph. For a quick estimate, multiply km/h by 0.6, or divide by 1.6.
How do I convert m/s to km/h?
Multiply by 3.6, because one meter per second is 3,600 meters per hour. 10 m/s is 36 km/h.
What is a knot?
One nautical mile per hour, which is exactly 1.852 km/h or about 1.151 mph.
Is 1 mph the same as 1.6 km/h?
Almost. One mph is exactly 1.609344 km/h, so 1.6 is a good rounded value.
What is 30 mph in km/h?
48.3 km/h. Close enough to 50 that a 30 mph zone and a 50 km/h zone feel the same from behind the wheel.