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.
km/h to mph
mph = km/h ÷ 1.609344
m/s to km/h
km/h = m/s × 3.6
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 |
How to use it
- 1Pick the unit you have on the left and the unit you want on the right.
- 2Type a value on either side. The other side updates as you type, and the swap button turns the conversion around.
- 3Read the result and the factor below it, or tap any unit in the list to convert into it. Copy the result or a link to share it.
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.